数学

闫增涛

2024-10-21 4a4c35cb4e9f00fef9694ca37ae25d303d77ad43

 src/books/mathBook/view/components/chapter003.vue

@@ -351,6 +351,38 @@
              </svg>
            </span>
          </p>
          <div v-if="isShowAnswer5" >
            <p><span class="zt-ls"><b>解</b></span>（1） 要使该函数有意义，必须满足</p>
            <p class="center">4<i>x</i>+7≠0，</p>
            <p>解得</p>
            <math display="block">
              <mi>x</mi>
              <mo>≠</mo>
              <mo>−</mo>
              <mfrac>
                <mn>7</mn>
                <mn>4</mn>
              </mfrac>
              <mo>.</mo>
            </math>
            <p>所以函数<i>f</i>（<i>x</i>）的定义域是<math display="0">
                <mrow data-mjx-texclass="INNER">
                  <mo data-mjx-texclass="OPEN">{</mo>
                  <mi>x</mi>
                  <mrow>
                    <mo stretchy="false">|</mo>
                  </mrow>
                  <mi>x</mi>
                  <mo>≠</mo>
                  <mo>−</mo>
                  <mfrac>
                    <mn>7</mn>
                    <mn>4</mn>
                  </mfrac>
                  <mo data-mjx-texclass="CLOSE">}</mo>
                </mrow>
              </math>.</p>
          </div>
          <p class="p-btn">
            <span>
              （2）<math display="0">
@@ -376,6 +408,12 @@
              </svg>
            </span>
          </p>
          <div v-if="isShowAnswer6" >
            <p> <span class="zt-ls"><b>解</b></span>（2） 要使该函数有意义，必须满足</p>
            <p class="center"><i>x</i>-3≥0，</p>
            <p>解得　<i>x</i>≥3.</p>
            <p>所以函数<i>f</i>（<i>x</i>）的定义域是{<i>x</i>|<i>x</i>≥3}.</p>
          </div>
          <p class="p-btn" >
            <span>
              （3） <math display="0">
@@ -411,46 +449,8 @@
              </svg>
            </span>
          </p>
          <div v-if="isShowAnswer5" >
            <p><span class="zt-ls"><b>解</b></span>（1） 要使该函数有意义，必须满足</p>
            <p class="center">4<i>x</i>+7≠0，</p>
            <p>解得</p>
            <math display="block">
              <mi>x</mi>
              <mo>≠</mo>
              <mo>−</mo>
              <mfrac>
                <mn>7</mn>
                <mn>4</mn>
              </mfrac>
              <mo>.</mo>
            </math>
            <p>所以函数<i>f</i>（<i>x</i>）的定义域是<math display="0">
                <mrow data-mjx-texclass="INNER">
                  <mo data-mjx-texclass="OPEN">{</mo>
                  <mi>x</mi>
                  <mrow>
                    <mo stretchy="false">|</mo>
                  </mrow>
                  <mi>x</mi>
                  <mo>≠</mo>
                  <mo>−</mo>
                  <mfrac>
                    <mn>7</mn>
                    <mn>4</mn>
                  </mfrac>
                  <mo data-mjx-texclass="CLOSE">}</mo>
                </mrow>
              </math>.</p>
          </div>
          <div v-if="isShowAnswer6" >
            <p>（2） 要使该函数有意义，必须满足</p>
            <p class="center"><i>x</i>-3≥0，</p>
            <p>解得　<i>x</i>≥3.</p>
            <p>所以函数<i>f</i>（<i>x</i>）的定义域是{<i>x</i>|<i>x</i>≥3}.</p>
          </div>
          <div v-if="isShowAnswer7" >
            <p>（3） 要使该函数有意义，必须满足</p>
            <p> <span class="zt-ls"><b>解</b></span>（3） 要使该函数有意义，必须满足</p>
            <math display="block">
              <mrow data-mjx-texclass="INNER">
                <mo data-mjx-texclass="OPEN">{</mo>
@@ -643,16 +643,6 @@
              </svg>
            </span>
          </p>
          <p class="p-btn" >
            <span>（2） 用图像法表示函数<i>s</i>=<i>f</i>（<i>t</i>）.</span>
            <span class="btn-box" @click="isShowAnswer12 = !isShowAnswer12">
              <svg xmlns="http://www.w3.org/2000/svg" width="16.501" height="16.501" viewBox="0 0 20.501 20.501">
                <path class="a"
                  d="M3344.717-15308.5H3337.4a10.186,10.186,0,0,1-7.25-3,10.185,10.185,0,0,1-3-7.25A10.262,10.262,0,0,1,3337.4-15329a10.26,10.26,0,0,1,10.249,10.248,10.129,10.129,0,0,1-2.2,6.341v3.177A.734.734,0,0,1,3344.717-15308.5Zm-9.606-7.29h4.493l.527,1.419c.071.182.156.386.254.608a2.428,2.428,0,0,0,.273.512.986.986,0,0,0,.315.262.971.971,0,0,0,.454.1,1.05,1.05,0,0,0,.773-.327,1.025,1.025,0,0,0,.319-.723,3.3,3.3,0,0,0-.277-1.051l-.062-.161-2.889-7.313c-.119-.321-.228-.607-.335-.873a2.972,2.972,0,0,0-.323-.616,1.56,1.56,0,0,0-.5-.469,1.552,1.552,0,0,0-.781-.181,1.535,1.535,0,0,0-.773.181,1.475,1.475,0,0,0-.5.477,3.674,3.674,0,0,0-.362.739l-.239.627-.054.135-2.824,7.355c-.095.229-.179.46-.25.688a1.529,1.529,0,0,0-.073.477.978.978,0,0,0,.323.72,1.039,1.039,0,0,0,.746.315.838.838,0,0,0,.716-.3,4.676,4.676,0,0,0,.466-.985l.062-.165.527-1.449Zm3.747-1.5h-3.293l1.812-5.124,1.481,5.123Z"
                  transform="translate(-3327.144 15329)" />
              </svg>
            </span>
          </p>
          <div v-if="isShowAnswer11" > 
            <p><span class="zt-ls"><b>解</b></span>（1） 因为该军舰从出发地驶入海港需要用时<math display="0">
                <mfrac>
@@ -670,7 +660,21 @@
            <p>所以，用解析法可将函数<i>s</i>=<i>f</i>（<i>t</i>）表示为</p>
            <p class="center"><i>s</i>=-45<i>t</i>+135，0≤<i>t</i>≤3.</p>
          </div>

          <p class="p-btn" >
            <span>（2） 用图像法表示函数<i>s</i>=<i>f</i>（<i>t</i>）.</span>
            <span class="btn-box" @click="isShowAnswer12 = !isShowAnswer12">
              <svg xmlns="http://www.w3.org/2000/svg" width="16.501" height="16.501" viewBox="0 0 20.501 20.501">
                <path class="a"
                  d="M3344.717-15308.5H3337.4a10.186,10.186,0,0,1-7.25-3,10.185,10.185,0,0,1-3-7.25A10.262,10.262,0,0,1,3337.4-15329a10.26,10.26,0,0,1,10.249,10.248,10.129,10.129,0,0,1-2.2,6.341v3.177A.734.734,0,0,1,3344.717-15308.5Zm-9.606-7.29h4.493l.527,1.419c.071.182.156.386.254.608a2.428,2.428,0,0,0,.273.512.986.986,0,0,0,.315.262.971.971,0,0,0,.454.1,1.05,1.05,0,0,0,.773-.327,1.025,1.025,0,0,0,.319-.723,3.3,3.3,0,0,0-.277-1.051l-.062-.161-2.889-7.313c-.119-.321-.228-.607-.335-.873a2.972,2.972,0,0,0-.323-.616,1.56,1.56,0,0,0-.5-.469,1.552,1.552,0,0,0-.781-.181,1.535,1.535,0,0,0-.773.181,1.475,1.475,0,0,0-.5.477,3.674,3.674,0,0,0-.362.739l-.239.627-.054.135-2.824,7.355c-.095.229-.179.46-.25.688a1.529,1.529,0,0,0-.073.477.978.978,0,0,0,.323.72,1.039,1.039,0,0,0,.746.315.838.838,0,0,0,.716-.3,4.676,4.676,0,0,0,.466-.985l.062-.165.527-1.449Zm3.747-1.5h-3.293l1.812-5.124,1.481,5.123Z"
                  transform="translate(-3327.144 15329)" />
              </svg>
            </span>
          </p>
          <div v-if="isShowAnswer12" >
            <p> <span class="zt-ls"><b>解</b></span>（2） 函数<i>s</i>=<i>f</i>（<i>t</i>）是一次函数，用图像法可将函数表示为图3-5.</p>
            <p class="center"><img class="img-c" alt="" src="../../assets/images/0088-3.jpg" /></p>
            <p class="img">图3-5</p>
          </div>
        </div>
      </div>
    </div>
@@ -683,11 +687,6 @@
          <li>上册</li>
        </ul>
        <div class="padding-116">
          <div v-if="isShowAnswer12" >
            <p>（2） 函数<i>s</i>=<i>f</i>（<i>t</i>）是一次函数，用图像法可将函数表示为图3-5.</p>
            <p class="center"><img class="img-c" alt="" src="../../assets/images/0088-3.jpg" /></p>
            <p class="img">图3-5</p>
          </div>
          <div class="bk-hzjl">
            <div class="bj1-hzjl">
              <p class="left"><img class="img-gn2" alt="" src="../../assets/images/hzjl.jpg" /></p>
@@ -901,6 +900,10 @@
              </svg>
            </span>
          </p>
          <div v-if="isShowAnswer13" >
            <p><span class="zt-ls"><b>解</b></span>（1） 因为-5＜0，所以<i>f</i>（-5）=-5+2=-3.</p>
            <p>因为4＞0，所以 <i>f</i>（4）=4<sup>2</sup>-3=13.</p>
          </div>
        </div>
      </div>
    </div>
@@ -923,6 +926,10 @@
              </svg>
            </span>
          </p>
          <div v-if="isShowAnswer14">
            <p>  <span class="zt-ls"><b>解</b></span>（2） 因为-1＜0，所以<i>f</i>（-1）=-1+2=1.</p>
            <p>又因为1＞0，所以<i>f</i>（<i>f</i>（-1））=<i>f</i>（1）=1<sup>2</sup>-3=-2.</p>
          </div>
          <div class="bk">
            <div class="bj1">
              <p class="left"><img class="img-gn1" alt="" src="../../assets/images/tbts.jpg" /></p>
@@ -930,14 +937,6 @@
            <p class="block">
              分段函数是一个函数，不能把它看成几个函数，只是在同一个函数的定义域内，不同的取值范围内对应不同的函数关系.它的定义域是各个解析式的自变量取值集合的并集，值域也是各个解析式的函数值集合的并集.它的图像也比较特殊，有时图像是不连续的.
            </p>
          </div>
          <div v-if="isShowAnswer13" >
            <p><span class="zt-ls"><b>解</b></span>（1） 因为-5＜0，所以<i>f</i>（-5）=-5+2=-3.</p>
            <p>因为4＞0，所以 <i>f</i>（4）=4<sup>2</sup>-3=13.</p>
          </div>
          <div v-if="isShowAnswer14">
            <p>（2） 因为-1＜0，所以<i>f</i>（-1）=-1+2=1.</p>
            <p>又因为1＞0，所以<i>f</i>（<i>f</i>（-1））=<i>f</i>（1）=1<sup>2</sup>-3=-2.</p>
          </div>
          <p>
            <span
@@ -955,26 +954,6 @@
          <p class="p-btn" >
            <span>（1） 用解析法表示<i>y</i>与<i>x</i>的函数关系，并画出函数的图像.</span>
            <span class="btn-box" @click="isShowAnswer15 = !isShowAnswer15">
              <svg xmlns="http://www.w3.org/2000/svg" width="16.501" height="16.501" viewBox="0 0 20.501 20.501">
                <path class="a"
                  d="M3344.717-15308.5H3337.4a10.186,10.186,0,0,1-7.25-3,10.185,10.185,0,0,1-3-7.25A10.262,10.262,0,0,1,3337.4-15329a10.26,10.26,0,0,1,10.249,10.248,10.129,10.129,0,0,1-2.2,6.341v3.177A.734.734,0,0,1,3344.717-15308.5Zm-9.606-7.29h4.493l.527,1.419c.071.182.156.386.254.608a2.428,2.428,0,0,0,.273.512.986.986,0,0,0,.315.262.971.971,0,0,0,.454.1,1.05,1.05,0,0,0,.773-.327,1.025,1.025,0,0,0,.319-.723,3.3,3.3,0,0,0-.277-1.051l-.062-.161-2.889-7.313c-.119-.321-.228-.607-.335-.873a2.972,2.972,0,0,0-.323-.616,1.56,1.56,0,0,0-.5-.469,1.552,1.552,0,0,0-.781-.181,1.535,1.535,0,0,0-.773.181,1.475,1.475,0,0,0-.5.477,3.674,3.674,0,0,0-.362.739l-.239.627-.054.135-2.824,7.355c-.095.229-.179.46-.25.688a1.529,1.529,0,0,0-.073.477.978.978,0,0,0,.323.72,1.039,1.039,0,0,0,.746.315.838.838,0,0,0,.716-.3,4.676,4.676,0,0,0,.466-.985l.062-.165.527-1.449Zm3.747-1.5h-3.293l1.812-5.124,1.481,5.123Z"
                  transform="translate(-3327.144 15329)" />
              </svg>
            </span>
          </p>
          <p class="p-btn" >
            <span>（2） 如果李某家10月的用电量是180 kW·h ，那么他家应该支付电费多少？</span>
            <span class="btn-box" @click="isShowAnswer16 = !isShowAnswer16">
              <svg xmlns="http://www.w3.org/2000/svg" width="16.501" height="16.501" viewBox="0 0 20.501 20.501">
                <path class="a"
                  d="M3344.717-15308.5H3337.4a10.186,10.186,0,0,1-7.25-3,10.185,10.185,0,0,1-3-7.25A10.262,10.262,0,0,1,3337.4-15329a10.26,10.26,0,0,1,10.249,10.248,10.129,10.129,0,0,1-2.2,6.341v3.177A.734.734,0,0,1,3344.717-15308.5Zm-9.606-7.29h4.493l.527,1.419c.071.182.156.386.254.608a2.428,2.428,0,0,0,.273.512.986.986,0,0,0,.315.262.971.971,0,0,0,.454.1,1.05,1.05,0,0,0,.773-.327,1.025,1.025,0,0,0,.319-.723,3.3,3.3,0,0,0-.277-1.051l-.062-.161-2.889-7.313c-.119-.321-.228-.607-.335-.873a2.972,2.972,0,0,0-.323-.616,1.56,1.56,0,0,0-.5-.469,1.552,1.552,0,0,0-.781-.181,1.535,1.535,0,0,0-.773.181,1.475,1.475,0,0,0-.5.477,3.674,3.674,0,0,0-.362.739l-.239.627-.054.135-2.824,7.355c-.095.229-.179.46-.25.688a1.529,1.529,0,0,0-.073.477.978.978,0,0,0,.323.72,1.039,1.039,0,0,0,.746.315.838.838,0,0,0,.716-.3,4.676,4.676,0,0,0,.466-.985l.062-.165.527-1.449Zm3.747-1.5h-3.293l1.812-5.124,1.481,5.123Z"
                  transform="translate(-3327.144 15329)" />
              </svg>
            </span>
          </p>
          <p class="p-btn" >
            <span>（3） 如果周某家12月支付电费294.26元，那么他家这个月的用电量是多少？</span>
            <span class="btn-box" @click="isShowAnswer17 = !isShowAnswer17">
              <svg xmlns="http://www.w3.org/2000/svg" width="16.501" height="16.501" viewBox="0 0 20.501 20.501">
                <path class="a"
                  d="M3344.717-15308.5H3337.4a10.186,10.186,0,0,1-7.25-3,10.185,10.185,0,0,1-3-7.25A10.262,10.262,0,0,1,3337.4-15329a10.26,10.26,0,0,1,10.249,10.248,10.129,10.129,0,0,1-2.2,6.341v3.177A.734.734,0,0,1,3344.717-15308.5Zm-9.606-7.29h4.493l.527,1.419c.071.182.156.386.254.608a2.428,2.428,0,0,0,.273.512.986.986,0,0,0,.315.262.971.971,0,0,0,.454.1,1.05,1.05,0,0,0,.773-.327,1.025,1.025,0,0,0,.319-.723,3.3,3.3,0,0,0-.277-1.051l-.062-.161-2.889-7.313c-.119-.321-.228-.607-.335-.873a2.972,2.972,0,0,0-.323-.616,1.56,1.56,0,0,0-.5-.469,1.552,1.552,0,0,0-.781-.181,1.535,1.535,0,0,0-.773.181,1.475,1.475,0,0,0-.5.477,3.674,3.674,0,0,0-.362.739l-.239.627-.054.135-2.824,7.355c-.095.229-.179.46-.25.688a1.529,1.529,0,0,0-.073.477.978.978,0,0,0,.323.72,1.039,1.039,0,0,0,.746.315.838.838,0,0,0,.716-.3,4.676,4.676,0,0,0,.466-.985l.062-.165.527-1.449Zm3.747-1.5h-3.293l1.812-5.124,1.481,5.123Z"
@@ -1053,6 +1032,36 @@
            <p class="img">图3-7</p>
            <p>这个函数的图像如图3-7所示.</p>
          </div>
          <p class="p-btn" >
            <span>（2） 如果李某家10月的用电量是180 kW·h ，那么他家应该支付电费多少？</span>
            <span class="btn-box" @click="isShowAnswer16 = !isShowAnswer16">
              <svg xmlns="http://www.w3.org/2000/svg" width="16.501" height="16.501" viewBox="0 0 20.501 20.501">
                <path class="a"
                  d="M3344.717-15308.5H3337.4a10.186,10.186,0,0,1-7.25-3,10.185,10.185,0,0,1-3-7.25A10.262,10.262,0,0,1,3337.4-15329a10.26,10.26,0,0,1,10.249,10.248,10.129,10.129,0,0,1-2.2,6.341v3.177A.734.734,0,0,1,3344.717-15308.5Zm-9.606-7.29h4.493l.527,1.419c.071.182.156.386.254.608a2.428,2.428,0,0,0,.273.512.986.986,0,0,0,.315.262.971.971,0,0,0,.454.1,1.05,1.05,0,0,0,.773-.327,1.025,1.025,0,0,0,.319-.723,3.3,3.3,0,0,0-.277-1.051l-.062-.161-2.889-7.313c-.119-.321-.228-.607-.335-.873a2.972,2.972,0,0,0-.323-.616,1.56,1.56,0,0,0-.5-.469,1.552,1.552,0,0,0-.781-.181,1.535,1.535,0,0,0-.773.181,1.475,1.475,0,0,0-.5.477,3.674,3.674,0,0,0-.362.739l-.239.627-.054.135-2.824,7.355c-.095.229-.179.46-.25.688a1.529,1.529,0,0,0-.073.477.978.978,0,0,0,.323.72,1.039,1.039,0,0,0,.746.315.838.838,0,0,0,.716-.3,4.676,4.676,0,0,0,.466-.985l.062-.165.527-1.449Zm3.747-1.5h-3.293l1.812-5.124,1.481,5.123Z"
                  transform="translate(-3327.144 15329)" />
              </svg>
            </span>
          </p>
          <div v-if="isShowAnswer16" >
            <p> <span class="zt-ls"><b>解</b></span>（2） 因为<i>x</i>=180＜200，<i>y</i>=0.52×180=93.60（元）.</p>
            <p>所以，李某家10月应该支付电费93.60元.</p>
          </div>
          <p class="p-btn" >
            <span>（3） 如果周某家12月支付电费294.26元，那么他家这个月的用电量是多少？</span>
            <span class="btn-box" @click="isShowAnswer17 = !isShowAnswer17">
              <svg xmlns="http://www.w3.org/2000/svg" width="16.501" height="16.501" viewBox="0 0 20.501 20.501">
                <path class="a"
                  d="M3344.717-15308.5H3337.4a10.186,10.186,0,0,1-7.25-3,10.185,10.185,0,0,1-3-7.25A10.262,10.262,0,0,1,3337.4-15329a10.26,10.26,0,0,1,10.249,10.248,10.129,10.129,0,0,1-2.2,6.341v3.177A.734.734,0,0,1,3344.717-15308.5Zm-9.606-7.29h4.493l.527,1.419c.071.182.156.386.254.608a2.428,2.428,0,0,0,.273.512.986.986,0,0,0,.315.262.971.971,0,0,0,.454.1,1.05,1.05,0,0,0,.773-.327,1.025,1.025,0,0,0,.319-.723,3.3,3.3,0,0,0-.277-1.051l-.062-.161-2.889-7.313c-.119-.321-.228-.607-.335-.873a2.972,2.972,0,0,0-.323-.616,1.56,1.56,0,0,0-.5-.469,1.552,1.552,0,0,0-.781-.181,1.535,1.535,0,0,0-.773.181,1.475,1.475,0,0,0-.5.477,3.674,3.674,0,0,0-.362.739l-.239.627-.054.135-2.824,7.355c-.095.229-.179.46-.25.688a1.529,1.529,0,0,0-.073.477.978.978,0,0,0,.323.72,1.039,1.039,0,0,0,.746.315.838.838,0,0,0,.716-.3,4.676,4.676,0,0,0,.466-.985l.062-.165.527-1.449Zm3.747-1.5h-3.293l1.812-5.124,1.481,5.123Z"
                  transform="translate(-3327.144 15329)" />
              </svg>
            </span>
          </p>
          <div v-if="isShowAnswer17" >
            <p> <span class="zt-ls"><b>解</b></span>（3） 周某家电费是294.26元，由图3-7可估得<i>x</i>＞400，因此</p>
            <p class="center">0.82<i>x</i>-110=294.26，</p>
            <p>解得<i>x</i>=493.</p>
            <p>所以，周某家12月的用电量为493 kW·h .</p>
          </div>
        </div>
      </div>
    </div>
@@ -1068,16 +1077,7 @@
          </li>
        </ul>
        <div class="padding-116">
          <div v-if="isShowAnswer16" >
            <p>（2） 因为<i>x</i>=180＜200，<i>y</i>=0.52×180=93.60（元）.</p>
            <p>所以，李某家10月应该支付电费93.60元.</p>
          </div>
          <div v-if="isShowAnswer17" >
            <p>（3） 周某家电费是294.26元，由图3-7可估得<i>x</i>＞400，因此</p>
            <p class="center">0.82<i>x</i>-110=294.26，</p>
            <p>解得<i>x</i>=493.</p>
            <p>所以，周某家12月的用电量为493 kW·h .</p>
          </div>

          <div class="bk-hzjl">
            <div class="bj1-hzjl">
              <p class="left"><img class="img-gn2" alt="" src="../../assets/images/hzjl.jpg" /></p>
@@ -1196,6 +1196,7 @@
              </svg>
            </span>
          </p>
          <p v-if="isShowAnswer18" ><span class="zt-ls"><b>解</b></span>（1） 由图可知，当<i>x</i>=2时，函数值最大，最大值是3；当<i>x</i>=6时，函数值最小，最小值是-3.</p>
          <p class="p-btn" >
            <span>（2） 说明该函数的单调区间及在每一个区间上的单调性.</span>
            <span class="btn-box" @click="isShowAnswer19 = !isShowAnswer19">
@@ -1208,8 +1209,9 @@
          </p>
          <p class="center"><img class="img-c" alt="" src="../../assets/images/0097-3.jpg" /></p>
          <p class="img">图3-11</p>
          <p v-if="isShowAnswer18" ><span class="zt-ls"><b>解</b></span>（1） 由图可知，当<i>x</i>=2时，函数值最大，最大值是3；当<i>x</i>=6时，函数值最小，最小值是-3.</p>
          <p v-if="isShowAnswer19" >（2）
          <p v-if="isShowAnswer19" >
            <span class="zt-ls"><b>解</b></span>
            （2）
            函数<i>y</i>=<i>f</i>（<i>x</i>）的单调区间有［-1，2］，［2，6］，［6，8］.函数<i>y</i>=<i>f</i>（<i>x</i>）在区间［-1，2］和［6，8］上都是增函数，在区间［2，6］上是减函数.
          </p>
        </div>
@@ -1241,32 +1243,6 @@
              </svg>
            </span>
          </p>
          <p class="p-btn" >
            <span>（2） 找出函数<i>f</i>（<i>x</i>）的单调区间；</span>
            <span class="btn-box" @click="isShowAnswer21 = !isShowAnswer21">
              <svg xmlns="http://www.w3.org/2000/svg" width="16.501" height="16.501" viewBox="0 0 20.501 20.501">
                <path class="a"
                  d="M3344.717-15308.5H3337.4a10.186,10.186,0,0,1-7.25-3,10.185,10.185,0,0,1-3-7.25A10.262,10.262,0,0,1,3337.4-15329a10.26,10.26,0,0,1,10.249,10.248,10.129,10.129,0,0,1-2.2,6.341v3.177A.734.734,0,0,1,3344.717-15308.5Zm-9.606-7.29h4.493l.527,1.419c.071.182.156.386.254.608a2.428,2.428,0,0,0,.273.512.986.986,0,0,0,.315.262.971.971,0,0,0,.454.1,1.05,1.05,0,0,0,.773-.327,1.025,1.025,0,0,0,.319-.723,3.3,3.3,0,0,0-.277-1.051l-.062-.161-2.889-7.313c-.119-.321-.228-.607-.335-.873a2.972,2.972,0,0,0-.323-.616,1.56,1.56,0,0,0-.5-.469,1.552,1.552,0,0,0-.781-.181,1.535,1.535,0,0,0-.773.181,1.475,1.475,0,0,0-.5.477,3.674,3.674,0,0,0-.362.739l-.239.627-.054.135-2.824,7.355c-.095.229-.179.46-.25.688a1.529,1.529,0,0,0-.073.477.978.978,0,0,0,.323.72,1.039,1.039,0,0,0,.746.315.838.838,0,0,0,.716-.3,4.676,4.676,0,0,0,.466-.985l.062-.165.527-1.449Zm3.747-1.5h-3.293l1.812-5.124,1.481,5.123Z"
                  transform="translate(-3327.144 15329)" />
              </svg>
            </span>
          </p>
          <p class="p-btn" >
            <span>（3） 当<i>x</i>∈［2，5］时，求函数<i>f</i>（<i>x</i>）的最大值和最小值.</span>
            <span class="btn-box" @click="isShowAnswer22 = !isShowAnswer22">
              <svg xmlns="http://www.w3.org/2000/svg" width="16.501" height="16.501" viewBox="0 0 20.501 20.501">
                <path class="a"
                  d="M3344.717-15308.5H3337.4a10.186,10.186,0,0,1-7.25-3,10.185,10.185,0,0,1-3-7.25A10.262,10.262,0,0,1,3337.4-15329a10.26,10.26,0,0,1,10.249,10.248,10.129,10.129,0,0,1-2.2,6.341v3.177A.734.734,0,0,1,3344.717-15308.5Zm-9.606-7.29h4.493l.527,1.419c.071.182.156.386.254.608a2.428,2.428,0,0,0,.273.512.986.986,0,0,0,.315.262.971.971,0,0,0,.454.1,1.05,1.05,0,0,0,.773-.327,1.025,1.025,0,0,0,.319-.723,3.3,3.3,0,0,0-.277-1.051l-.062-.161-2.889-7.313c-.119-.321-.228-.607-.335-.873a2.972,2.972,0,0,0-.323-.616,1.56,1.56,0,0,0-.5-.469,1.552,1.552,0,0,0-.781-.181,1.535,1.535,0,0,0-.773.181,1.475,1.475,0,0,0-.5.477,3.674,3.674,0,0,0-.362.739l-.239.627-.054.135-2.824,7.355c-.095.229-.179.46-.25.688a1.529,1.529,0,0,0-.073.477.978.978,0,0,0,.323.72,1.039,1.039,0,0,0,.746.315.838.838,0,0,0,.716-.3,4.676,4.676,0,0,0,.466-.985l.062-.165.527-1.449Zm3.747-1.5h-3.293l1.812-5.124,1.481,5.123Z"
                  transform="translate(-3327.144 15329)" />
              </svg>
            </span>
          </p>
          <div class="bk">
            <div class="bj1">
              <p class="left"><img class="img-gn1" alt="" src="../../assets/images/tbts.jpg" /></p>
            </div>
            <p class="block">函数的单调性是对定义域内某个区间而言的.一个函数在其定义域上不一定具有单调性，但是在定义域内的子区间上可能具有单调性，这就是函数单调性的局部性质.</p>
          </div>
          <div v-if="isShowAnswer20" >
            <p><span class="zt-ls"><b>解</b></span>（1） 二次函数<i>y</i>=<i>ax</i><sup>2</sup>+<i>bx</i>+<i>c</i>的对称轴方程是<math
                display="0">
@@ -1398,11 +1374,37 @@
            </math>
            <p>因此，函数<i>f</i>（<i>x</i>）的对称轴方程是<i>x</i>=1，顶点坐标是（1，4）.</p>
          </div>
          <p v-if="isShowAnswer21" >（2） 由图像可知，函数<i>f</i>（<i>x</i>）的增区间是（-∞，1］，减区间是［1，+∞）.</p>
          <p class="p-btn" >
            <span>（2） 找出函数<i>f</i>（<i>x</i>）的单调区间；</span>
            <span class="btn-box" @click="isShowAnswer21 = !isShowAnswer21">
              <svg xmlns="http://www.w3.org/2000/svg" width="16.501" height="16.501" viewBox="0 0 20.501 20.501">
                <path class="a"
                  d="M3344.717-15308.5H3337.4a10.186,10.186,0,0,1-7.25-3,10.185,10.185,0,0,1-3-7.25A10.262,10.262,0,0,1,3337.4-15329a10.26,10.26,0,0,1,10.249,10.248,10.129,10.129,0,0,1-2.2,6.341v3.177A.734.734,0,0,1,3344.717-15308.5Zm-9.606-7.29h4.493l.527,1.419c.071.182.156.386.254.608a2.428,2.428,0,0,0,.273.512.986.986,0,0,0,.315.262.971.971,0,0,0,.454.1,1.05,1.05,0,0,0,.773-.327,1.025,1.025,0,0,0,.319-.723,3.3,3.3,0,0,0-.277-1.051l-.062-.161-2.889-7.313c-.119-.321-.228-.607-.335-.873a2.972,2.972,0,0,0-.323-.616,1.56,1.56,0,0,0-.5-.469,1.552,1.552,0,0,0-.781-.181,1.535,1.535,0,0,0-.773.181,1.475,1.475,0,0,0-.5.477,3.674,3.674,0,0,0-.362.739l-.239.627-.054.135-2.824,7.355c-.095.229-.179.46-.25.688a1.529,1.529,0,0,0-.073.477.978.978,0,0,0,.323.72,1.039,1.039,0,0,0,.746.315.838.838,0,0,0,.716-.3,4.676,4.676,0,0,0,.466-.985l.062-.165.527-1.449Zm3.747-1.5h-3.293l1.812-5.124,1.481,5.123Z"
                  transform="translate(-3327.144 15329)" />
              </svg>
            </span>
          </p>
          <p v-if="isShowAnswer21" > <span class="zt-ls"><b>解</b></span>（2） 由图像可知，函数<i>f</i>（<i>x</i>）的增区间是（-∞，1］，减区间是［1，+∞）.</p>
          <p class="p-btn" >
            <span>（3） 当<i>x</i>∈［2，5］时，求函数<i>f</i>（<i>x</i>）的最大值和最小值.</span>
            <span class="btn-box" @click="isShowAnswer22 = !isShowAnswer22">
              <svg xmlns="http://www.w3.org/2000/svg" width="16.501" height="16.501" viewBox="0 0 20.501 20.501">
                <path class="a"
                  d="M3344.717-15308.5H3337.4a10.186,10.186,0,0,1-7.25-3,10.185,10.185,0,0,1-3-7.25A10.262,10.262,0,0,1,3337.4-15329a10.26,10.26,0,0,1,10.249,10.248,10.129,10.129,0,0,1-2.2,6.341v3.177A.734.734,0,0,1,3344.717-15308.5Zm-9.606-7.29h4.493l.527,1.419c.071.182.156.386.254.608a2.428,2.428,0,0,0,.273.512.986.986,0,0,0,.315.262.971.971,0,0,0,.454.1,1.05,1.05,0,0,0,.773-.327,1.025,1.025,0,0,0,.319-.723,3.3,3.3,0,0,0-.277-1.051l-.062-.161-2.889-7.313c-.119-.321-.228-.607-.335-.873a2.972,2.972,0,0,0-.323-.616,1.56,1.56,0,0,0-.5-.469,1.552,1.552,0,0,0-.781-.181,1.535,1.535,0,0,0-.773.181,1.475,1.475,0,0,0-.5.477,3.674,3.674,0,0,0-.362.739l-.239.627-.054.135-2.824,7.355c-.095.229-.179.46-.25.688a1.529,1.529,0,0,0-.073.477.978.978,0,0,0,.323.72,1.039,1.039,0,0,0,.746.315.838.838,0,0,0,.716-.3,4.676,4.676,0,0,0,.466-.985l.062-.165.527-1.449Zm3.747-1.5h-3.293l1.812-5.124,1.481,5.123Z"
                  transform="translate(-3327.144 15329)" />
              </svg>
            </span>
          </p>
          <div v-if="isShowAnswer22" >
            <p>（3） 因为［2，5］⫋［1，+∞），且函数在区间［1，+∞）上是减函数，所以当<i>x</i>∈［2，5］时，</p>
            <p> <span class="zt-ls"><b>解</b></span>（3） 因为［2，5］⫋［1，+∞），且函数在区间［1，+∞）上是减函数，所以当<i>x</i>∈［2，5］时，</p>
            <p>函数<i>f</i>（<i>x</i>）的最大值是<i>f</i>（2）=-2<sup>2</sup>+2×2+3=3，</p>
            <p>函数<i>f</i>（<i>x</i>）的最小值是<i>f</i>（5）=-5<sup>2</sup>+2×5+3=-12.</p>
          </div>
          <div class="bk">
            <div class="bj1">
              <p class="left"><img class="img-gn1" alt="" src="../../assets/images/tbts.jpg" /></p>
            </div>
            <p class="block">函数的单调性是对定义域内某个区间而言的.一个函数在其定义域上不一定具有单调性，但是在定义域内的子区间上可能具有单调性，这就是函数单调性的局部性质.</p>
          </div>
          <p class="p-btn" >
            <span>
@@ -1416,7 +1418,6 @@
              </svg>
            </span>
          </p>
          <iframe src="https://www.geogebra.org/calculator" frameborder="0" class="iframe-box"></iframe>
          <div v-if="isShowAnswer23" >
            <p><span class="zt-ls"><b>解</b></span>
              任取<i>x</i><sub>1</sub>，<i>x</i><sub>2</sub>∈（-∞，+∞），且<i>x</i><sub>1</sub>＜<i>x</i><sub>2</sub>，那么</p>
@@ -1435,6 +1436,7 @@
            <p class="center"><img class="img-b" alt="" src="../../assets/images/0098-5.jpg" /></p>
            <p class="img">图3-13</p>
          </div>
          <iframe src="https://www.geogebra.org/calculator" frameborder="0" class="iframe-box"></iframe>
        </div>
      </div>
    </div>
@@ -1943,6 +1945,15 @@
              </svg>
            </span>
          </p>
          <div v-if="isShowAnswer26" >
            <p><span class="zt-ls"><b>解</b></span>（1）
              函数<i>f</i>（<i>x</i>）=<i>x</i><sup>3</sup>+<i>x</i>的定义域是<b>R</b>，对任意<i>x</i>∈<b>R</b>，都有-<i>x</i>∈<b>R</b>，且
            </p>
            <p class="center">
              <i>f</i>（-<i>x</i>）=（-<i>x</i>）<sup>3</sup>+（-<i>x</i>）=-<i>x</i><sup>3</sup>-<i>x</i>=-（<i>x</i><sup>3</sup>+<i>x</i>）=-<i>f</i>（<i>x</i>）.
            </p>
            <p>所以，函数<i>f</i>（<i>x</i>）=<i>x</i><sup>3</sup>+<i>x</i>是奇函数.</p>
          </div>
          <p class="p-btn" >
            <span>
              （2） <math display="0">
@@ -1969,27 +1980,9 @@
              </svg>
            </span>
          </p>
          <p class="p-btn" >
            <span>（3） <i>f</i>（<i>x</i>）=<i>x</i>+|<i>x</i>|.</span>
            <span class="btn-box" @click="isShowAnswer28 = !isShowAnswer28">
              <svg xmlns="http://www.w3.org/2000/svg" width="16.501" height="16.501" viewBox="0 0 20.501 20.501">
                <path class="a"
                  d="M3344.717-15308.5H3337.4a10.186,10.186,0,0,1-7.25-3,10.185,10.185,0,0,1-3-7.25A10.262,10.262,0,0,1,3337.4-15329a10.26,10.26,0,0,1,10.249,10.248,10.129,10.129,0,0,1-2.2,6.341v3.177A.734.734,0,0,1,3344.717-15308.5Zm-9.606-7.29h4.493l.527,1.419c.071.182.156.386.254.608a2.428,2.428,0,0,0,.273.512.986.986,0,0,0,.315.262.971.971,0,0,0,.454.1,1.05,1.05,0,0,0,.773-.327,1.025,1.025,0,0,0,.319-.723,3.3,3.3,0,0,0-.277-1.051l-.062-.161-2.889-7.313c-.119-.321-.228-.607-.335-.873a2.972,2.972,0,0,0-.323-.616,1.56,1.56,0,0,0-.5-.469,1.552,1.552,0,0,0-.781-.181,1.535,1.535,0,0,0-.773.181,1.475,1.475,0,0,0-.5.477,3.674,3.674,0,0,0-.362.739l-.239.627-.054.135-2.824,7.355c-.095.229-.179.46-.25.688a1.529,1.529,0,0,0-.073.477.978.978,0,0,0,.323.72,1.039,1.039,0,0,0,.746.315.838.838,0,0,0,.716-.3,4.676,4.676,0,0,0,.466-.985l.062-.165.527-1.449Zm3.747-1.5h-3.293l1.812-5.124,1.481,5.123Z"
                  transform="translate(-3327.144 15329)" />
              </svg>
            </span>
          </p>
          <div v-if="isShowAnswer26" >
            <p><span class="zt-ls"><b>解</b></span>（1）
              函数<i>f</i>（<i>x</i>）=<i>x</i><sup>3</sup>+<i>x</i>的定义域是<b>R</b>，对任意<i>x</i>∈<b>R</b>，都有-<i>x</i>∈<b>R</b>，且
            </p>
            <p class="center">
              <i>f</i>（-<i>x</i>）=（-<i>x</i>）<sup>3</sup>+（-<i>x</i>）=-<i>x</i><sup>3</sup>-<i>x</i>=-（<i>x</i><sup>3</sup>+<i>x</i>）=-<i>f</i>（<i>x</i>）.
            </p>
            <p>所以，函数<i>f</i>（<i>x</i>）=<i>x</i><sup>3</sup>+<i>x</i>是奇函数.</p>
          </div>
          <div v-if="isShowAnswer27" >
            <p>（2）
            <p>
              <span class="zt-ls"><b>解</b></span>（2）
              要使函数<i>f</i>（<i>x</i>）有意义，必须满足<i>x</i>≠0，所以函数<i>f</i>（<i>x</i>）的定义域是<i>D</i>={<i>x</i>|<i>x</i>≠0}，对任意<i>x</i>∈<i>D</i>，都有-<i>x</i>∈<i>D</i>，且
            </p>
            <math display="block">
@@ -2051,8 +2044,18 @@
              </math>是奇函数.
            </p>
          </div>
          <p class="p-btn" >
            <span>（3） <i>f</i>（<i>x</i>）=<i>x</i>+|<i>x</i>|.</span>
            <span class="btn-box" @click="isShowAnswer28 = !isShowAnswer28">
              <svg xmlns="http://www.w3.org/2000/svg" width="16.501" height="16.501" viewBox="0 0 20.501 20.501">
                <path class="a"
                  d="M3344.717-15308.5H3337.4a10.186,10.186,0,0,1-7.25-3,10.185,10.185,0,0,1-3-7.25A10.262,10.262,0,0,1,3337.4-15329a10.26,10.26,0,0,1,10.249,10.248,10.129,10.129,0,0,1-2.2,6.341v3.177A.734.734,0,0,1,3344.717-15308.5Zm-9.606-7.29h4.493l.527,1.419c.071.182.156.386.254.608a2.428,2.428,0,0,0,.273.512.986.986,0,0,0,.315.262.971.971,0,0,0,.454.1,1.05,1.05,0,0,0,.773-.327,1.025,1.025,0,0,0,.319-.723,3.3,3.3,0,0,0-.277-1.051l-.062-.161-2.889-7.313c-.119-.321-.228-.607-.335-.873a2.972,2.972,0,0,0-.323-.616,1.56,1.56,0,0,0-.5-.469,1.552,1.552,0,0,0-.781-.181,1.535,1.535,0,0,0-.773.181,1.475,1.475,0,0,0-.5.477,3.674,3.674,0,0,0-.362.739l-.239.627-.054.135-2.824,7.355c-.095.229-.179.46-.25.688a1.529,1.529,0,0,0-.073.477.978.978,0,0,0,.323.72,1.039,1.039,0,0,0,.746.315.838.838,0,0,0,.716-.3,4.676,4.676,0,0,0,.466-.985l.062-.165.527-1.449Zm3.747-1.5h-3.293l1.812-5.124,1.481,5.123Z"
                  transform="translate(-3327.144 15329)" />
              </svg>
            </span>
          </p>
          <div v-if="isShowAnswer28"  >
            <p >（3） 函数<i>f</i>（<i>x</i>）=<i>x</i>+|<i>x</i>|的定义域是<b>R</b>，对任意<i>x</i>∈<b>R</b>，都有-<i>x</i>∈<b>R</b>，但是</p>
            <p > <span class="zt-ls"><b>解</b></span>（3） 函数<i>f</i>（<i>x</i>）=<i>x</i>+|<i>x</i>|的定义域是<b>R</b>，对任意<i>x</i>∈<b>R</b>，都有-<i>x</i>∈<b>R</b>，但是</p>
            <p class="center">
              <i>f</i>（-<i>x</i>）=（-<i>x</i>）+|-<i>x</i>|=-<i>x</i>+|<i>x</i>|=-（<i>x</i>-|<i>x</i>|）≠-<i>f</i>（<i>x</i>）.
            </p>
@@ -2091,6 +2094,13 @@
              </svg>
            </span>
          </p>
          <div v-if="isShowAnswer29" >
            <p><span class="zt-ls"><b>解</b></span>（1）
              <i>f</i>（<i>x</i>）的定义域是<b>R</b>，对任意<i>x</i>∈<b>R</b>，都有-<i>x</i>∈<b>R</b>，且
            </p>
            <p class="center"><i>f</i>（-<i>x</i>）=（-<i>x</i>）<sup>4</sup>=<i>x</i><sup>4</sup>=<i>f</i>（<i>x</i>），</p>
            <p>所以，函数<i>f</i>（<i>x</i>）=<i>x</i><sup>4</sup>是偶函数.</p>
          </div>
          <p class="p-btn">
            <span>
              （2） <math display="0">
@@ -2118,55 +2128,9 @@
              </svg>
            </span>
          </p>
          <p class="p-btn">
            <span>
              （3） <i>f</i>（<i>x</i>）=<i>x</i><sup>2</sup>+<i>x</i>；
            </span>
            <span class="btn-box" @click="isShowAnswer31 = !isShowAnswer31">
              <svg xmlns="http://www.w3.org/2000/svg" width="16.501" height="16.501" viewBox="0 0 20.501 20.501">
                <path class="a"
                  d="M3344.717-15308.5H3337.4a10.186,10.186,0,0,1-7.25-3,10.185,10.185,0,0,1-3-7.25A10.262,10.262,0,0,1,3337.4-15329a10.26,10.26,0,0,1,10.249,10.248,10.129,10.129,0,0,1-2.2,6.341v3.177A.734.734,0,0,1,3344.717-15308.5Zm-9.606-7.29h4.493l.527,1.419c.071.182.156.386.254.608a2.428,2.428,0,0,0,.273.512.986.986,0,0,0,.315.262.971.971,0,0,0,.454.1,1.05,1.05,0,0,0,.773-.327,1.025,1.025,0,0,0,.319-.723,3.3,3.3,0,0,0-.277-1.051l-.062-.161-2.889-7.313c-.119-.321-.228-.607-.335-.873a2.972,2.972,0,0,0-.323-.616,1.56,1.56,0,0,0-.5-.469,1.552,1.552,0,0,0-.781-.181,1.535,1.535,0,0,0-.773.181,1.475,1.475,0,0,0-.5.477,3.674,3.674,0,0,0-.362.739l-.239.627-.054.135-2.824,7.355c-.095.229-.179.46-.25.688a1.529,1.529,0,0,0-.073.477.978.978,0,0,0,.323.72,1.039,1.039,0,0,0,.746.315.838.838,0,0,0,.716-.3,4.676,4.676,0,0,0,.466-.985l.062-.165.527-1.449Zm3.747-1.5h-3.293l1.812-5.124,1.481,5.123Z"
                  transform="translate(-3327.144 15329)" />
              </svg>
            </span>
          </p>
          <p class="p-btn" >
            <span>
              （4）<math display="0">
                <mi>f</mi>
                <mrow data-mjx-texclass="INNER">
                  <mo data-mjx-texclass="OPEN">(</mo>
                  <mi>x</mi>
                  <mo data-mjx-texclass="CLOSE">)</mo>
                </mrow>
                <mo>=</mo>
                <mfrac>
                  <mn>1</mn>
                  <mrow>
                    <mi>x</mi>
                    <mo>−</mo>
                    <mn>1</mn>
                  </mrow>
                </mfrac>
              </math>.
            </span>
            <span class="btn-box" @click="isShowAnswer32 = !isShowAnswer32">
              <svg xmlns="http://www.w3.org/2000/svg" width="16.501" height="16.501" viewBox="0 0 20.501 20.501">
                <path class="a"
                  d="M3344.717-15308.5H3337.4a10.186,10.186,0,0,1-7.25-3,10.185,10.185,0,0,1-3-7.25A10.262,10.262,0,0,1,3337.4-15329a10.26,10.26,0,0,1,10.249,10.248,10.129,10.129,0,0,1-2.2,6.341v3.177A.734.734,0,0,1,3344.717-15308.5Zm-9.606-7.29h4.493l.527,1.419c.071.182.156.386.254.608a2.428,2.428,0,0,0,.273.512.986.986,0,0,0,.315.262.971.971,0,0,0,.454.1,1.05,1.05,0,0,0,.773-.327,1.025,1.025,0,0,0,.319-.723,3.3,3.3,0,0,0-.277-1.051l-.062-.161-2.889-7.313c-.119-.321-.228-.607-.335-.873a2.972,2.972,0,0,0-.323-.616,1.56,1.56,0,0,0-.5-.469,1.552,1.552,0,0,0-.781-.181,1.535,1.535,0,0,0-.773.181,1.475,1.475,0,0,0-.5.477,3.674,3.674,0,0,0-.362.739l-.239.627-.054.135-2.824,7.355c-.095.229-.179.46-.25.688a1.529,1.529,0,0,0-.073.477.978.978,0,0,0,.323.72,1.039,1.039,0,0,0,.746.315.838.838,0,0,0,.716-.3,4.676,4.676,0,0,0,.466-.985l.062-.165.527-1.449Zm3.747-1.5h-3.293l1.812-5.124,1.481,5.123Z"
                  transform="translate(-3327.144 15329)" />
              </svg>
            </span>
          </p>
          <div v-if="isShowAnswer29" >
            <p><span class="zt-ls"><b>解</b></span>（1）
              <i>f</i>（<i>x</i>）的定义域是<b>R</b>，对任意<i>x</i>∈<b>R</b>，都有-<i>x</i>∈<b>R</b>，且
            </p>
            <p class="center"><i>f</i>（-<i>x</i>）=（-<i>x</i>）<sup>4</sup>=<i>x</i><sup>4</sup>=<i>f</i>（<i>x</i>），</p>
            <p>所以，函数<i>f</i>（<i>x</i>）=<i>x</i><sup>4</sup>是偶函数.</p>
          </div>
          <div v-if="isShowAnswer30" >
            <p>（2）
            <p>
              <span class="zt-ls"><b>解</b></span>（2）
              要使函数<i>f</i>（<i>x</i>）有意义，必须满足<i>x</i>≠0，所以函数<i>f</i>（<i>x</i>）的定义域是<i>D</i>={<i>x</i>|<i>x</i>≠0}，对任意<i>x</i>∈<i>D</i>，都有-<i>x</i>∈<i>D</i>，
              且</p>
            <math display="block">
@@ -2230,18 +2194,57 @@
                </mfrac>
              </math>是奇函数.
            </p>

          </div>
          <p class="p-btn">
            <span>
              （3） <i>f</i>（<i>x</i>）=<i>x</i><sup>2</sup>+<i>x</i>；
            </span>
            <span class="btn-box" @click="isShowAnswer31 = !isShowAnswer31">
              <svg xmlns="http://www.w3.org/2000/svg" width="16.501" height="16.501" viewBox="0 0 20.501 20.501">
                <path class="a"
                  d="M3344.717-15308.5H3337.4a10.186,10.186,0,0,1-7.25-3,10.185,10.185,0,0,1-3-7.25A10.262,10.262,0,0,1,3337.4-15329a10.26,10.26,0,0,1,10.249,10.248,10.129,10.129,0,0,1-2.2,6.341v3.177A.734.734,0,0,1,3344.717-15308.5Zm-9.606-7.29h4.493l.527,1.419c.071.182.156.386.254.608a2.428,2.428,0,0,0,.273.512.986.986,0,0,0,.315.262.971.971,0,0,0,.454.1,1.05,1.05,0,0,0,.773-.327,1.025,1.025,0,0,0,.319-.723,3.3,3.3,0,0,0-.277-1.051l-.062-.161-2.889-7.313c-.119-.321-.228-.607-.335-.873a2.972,2.972,0,0,0-.323-.616,1.56,1.56,0,0,0-.5-.469,1.552,1.552,0,0,0-.781-.181,1.535,1.535,0,0,0-.773.181,1.475,1.475,0,0,0-.5.477,3.674,3.674,0,0,0-.362.739l-.239.627-.054.135-2.824,7.355c-.095.229-.179.46-.25.688a1.529,1.529,0,0,0-.073.477.978.978,0,0,0,.323.72,1.039,1.039,0,0,0,.746.315.838.838,0,0,0,.716-.3,4.676,4.676,0,0,0,.466-.985l.062-.165.527-1.449Zm3.747-1.5h-3.293l1.812-5.124,1.481,5.123Z"
                  transform="translate(-3327.144 15329)" />
              </svg>
            </span>
          </p>
          <div v-if="isShowAnswer31" >
            <p>（3）
            <p> <span class="zt-ls"><b>解</b></span>（3）
              函数<i>f</i>（<i>x</i>）=<i>x</i><sup>2</sup>+<i>x</i>的定义域是<b>R</b>，对任意<i>x</i>∈<b>R</b>，都有-<i>x</i>∈<b>R</b>，且
            </p>
            <p class="center"><i>f</i>（-<i>x</i>）=（-<i>x</i>）<sup>2</sup>+（-<i>x</i>）=<i>x</i><sup>2</sup>-<i>x</i>，</p>
            <p>但　<i>f</i>（-<i>x</i>）≠<i>f</i>（<i>x</i>），且<i>f</i>（-<i>x</i>）≠-<i>f</i>（<i>x</i>），</p>
            <p>所以，函数<i>f</i>（<i>x</i>）=<i>x</i><sup>2</sup>+<i>x</i>既不是奇函数，也不是偶函数.</p>
          </div>
          <p class="p-btn" >
            <span>
              （4）<math display="0">
                <mi>f</mi>
                <mrow data-mjx-texclass="INNER">
                  <mo data-mjx-texclass="OPEN">(</mo>
                  <mi>x</mi>
                  <mo data-mjx-texclass="CLOSE">)</mo>
                </mrow>
                <mo>=</mo>
                <mfrac>
                  <mn>1</mn>
                  <mrow>
                    <mi>x</mi>
                    <mo>−</mo>
                    <mn>1</mn>
                  </mrow>
                </mfrac>
              </math>.
            </span>
            <span class="btn-box" @click="isShowAnswer32 = !isShowAnswer32">
              <svg xmlns="http://www.w3.org/2000/svg" width="16.501" height="16.501" viewBox="0 0 20.501 20.501">
                <path class="a"
                  d="M3344.717-15308.5H3337.4a10.186,10.186,0,0,1-7.25-3,10.185,10.185,0,0,1-3-7.25A10.262,10.262,0,0,1,3337.4-15329a10.26,10.26,0,0,1,10.249,10.248,10.129,10.129,0,0,1-2.2,6.341v3.177A.734.734,0,0,1,3344.717-15308.5Zm-9.606-7.29h4.493l.527,1.419c.071.182.156.386.254.608a2.428,2.428,0,0,0,.273.512.986.986,0,0,0,.315.262.971.971,0,0,0,.454.1,1.05,1.05,0,0,0,.773-.327,1.025,1.025,0,0,0,.319-.723,3.3,3.3,0,0,0-.277-1.051l-.062-.161-2.889-7.313c-.119-.321-.228-.607-.335-.873a2.972,2.972,0,0,0-.323-.616,1.56,1.56,0,0,0-.5-.469,1.552,1.552,0,0,0-.781-.181,1.535,1.535,0,0,0-.773.181,1.475,1.475,0,0,0-.5.477,3.674,3.674,0,0,0-.362.739l-.239.627-.054.135-2.824,7.355c-.095.229-.179.46-.25.688a1.529,1.529,0,0,0-.073.477.978.978,0,0,0,.323.72,1.039,1.039,0,0,0,.746.315.838.838,0,0,0,.716-.3,4.676,4.676,0,0,0,.466-.985l.062-.165.527-1.449Zm3.747-1.5h-3.293l1.812-5.124,1.481,5.123Z"
                  transform="translate(-3327.144 15329)" />
              </svg>
            </span>
          </p>
          <div v-if="isShowAnswer32" >
            <p>（4）
            <p> <span class="zt-ls"><b>解</b></span>（4）
              要使函数<i>f</i>（<i>x</i>）有意义，必须满足<i>x</i>-1≠0，所以函数<i>f</i>（<i>x</i>）的定义域是<i>D</i>={<i>x</i>|<i>x</i>≠1}，对任意<i>x</i>∈<i>D</i>，不都有-<i>x</i>∈<i>D</i>成立.
            </p>
            <p>所以，函数<math display="0">
@@ -2357,27 +2360,6 @@
              </svg>
            </span>
          </p>
          <p class="p-btn" >
            <span>（2） 画出函数<i>y</i>=<i>f</i>（<i>x</i>）的图像；</span>
            <span class="btn-box" @click="isShowAnswer34 = !isShowAnswer34">
              <svg xmlns="http://www.w3.org/2000/svg" width="16.501" height="16.501" viewBox="0 0 20.501 20.501">
                <path class="a"
                  d="M3344.717-15308.5H3337.4a10.186,10.186,0,0,1-7.25-3,10.185,10.185,0,0,1-3-7.25A10.262,10.262,0,0,1,3337.4-15329a10.26,10.26,0,0,1,10.249,10.248,10.129,10.129,0,0,1-2.2,6.341v3.177A.734.734,0,0,1,3344.717-15308.5Zm-9.606-7.29h4.493l.527,1.419c.071.182.156.386.254.608a2.428,2.428,0,0,0,.273.512.986.986,0,0,0,.315.262.971.971,0,0,0,.454.1,1.05,1.05,0,0,0,.773-.327,1.025,1.025,0,0,0,.319-.723,3.3,3.3,0,0,0-.277-1.051l-.062-.161-2.889-7.313c-.119-.321-.228-.607-.335-.873a2.972,2.972,0,0,0-.323-.616,1.56,1.56,0,0,0-.5-.469,1.552,1.552,0,0,0-.781-.181,1.535,1.535,0,0,0-.773.181,1.475,1.475,0,0,0-.5.477,3.674,3.674,0,0,0-.362.739l-.239.627-.054.135-2.824,7.355c-.095.229-.179.46-.25.688a1.529,1.529,0,0,0-.073.477.978.978,0,0,0,.323.72,1.039,1.039,0,0,0,.746.315.838.838,0,0,0,.716-.3,4.676,4.676,0,0,0,.466-.985l.062-.165.527-1.449Zm3.747-1.5h-3.293l1.812-5.124,1.481,5.123Z"
                  transform="translate(-3327.144 15329)" />
              </svg>
            </span>
          </p>
          <iframe src="https://www.geogebra.org/calculator" frameborder="0" class="iframe-box"></iframe>
          <p class="p-btn" >
            <span>（3） 小李在返回A城途中，15：00刚好接到家人的电话，这时他距离A城多少千米？</span>
            <span class="btn-box" @click="isShowAnswer35 = !isShowAnswer35">
              <svg xmlns="http://www.w3.org/2000/svg" width="16.501" height="16.501" viewBox="0 0 20.501 20.501">
                <path class="a"
                  d="M3344.717-15308.5H3337.4a10.186,10.186,0,0,1-7.25-3,10.185,10.185,0,0,1-3-7.25A10.262,10.262,0,0,1,3337.4-15329a10.26,10.26,0,0,1,10.249,10.248,10.129,10.129,0,0,1-2.2,6.341v3.177A.734.734,0,0,1,3344.717-15308.5Zm-9.606-7.29h4.493l.527,1.419c.071.182.156.386.254.608a2.428,2.428,0,0,0,.273.512.986.986,0,0,0,.315.262.971.971,0,0,0,.454.1,1.05,1.05,0,0,0,.773-.327,1.025,1.025,0,0,0,.319-.723,3.3,3.3,0,0,0-.277-1.051l-.062-.161-2.889-7.313c-.119-.321-.228-.607-.335-.873a2.972,2.972,0,0,0-.323-.616,1.56,1.56,0,0,0-.5-.469,1.552,1.552,0,0,0-.781-.181,1.535,1.535,0,0,0-.773.181,1.475,1.475,0,0,0-.5.477,3.674,3.674,0,0,0-.362.739l-.239.627-.054.135-2.824,7.355c-.095.229-.179.46-.25.688a1.529,1.529,0,0,0-.073.477.978.978,0,0,0,.323.72,1.039,1.039,0,0,0,.746.315.838.838,0,0,0,.716-.3,4.676,4.676,0,0,0,.466-.985l.062-.165.527-1.449Zm3.747-1.5h-3.293l1.812-5.124,1.481,5.123Z"
                  transform="translate(-3327.144 15329)" />
              </svg>
            </span>
          </p>
          <div v-if="isShowAnswer33" >
            <p><span class="zt-ls"><b>解</b></span>（1） 小李从A城出发到B 城用时<math display="0">
                <mfrac>
@@ -2462,13 +2444,34 @@
              </math>.
            </p>
          </div>
          <p class="p-btn" >
            <span>（2） 画出函数<i>y</i>=<i>f</i>（<i>x</i>）的图像；</span>
            <span class="btn-box" @click="isShowAnswer34 = !isShowAnswer34">
              <svg xmlns="http://www.w3.org/2000/svg" width="16.501" height="16.501" viewBox="0 0 20.501 20.501">
                <path class="a"
                  d="M3344.717-15308.5H3337.4a10.186,10.186,0,0,1-7.25-3,10.185,10.185,0,0,1-3-7.25A10.262,10.262,0,0,1,3337.4-15329a10.26,10.26,0,0,1,10.249,10.248,10.129,10.129,0,0,1-2.2,6.341v3.177A.734.734,0,0,1,3344.717-15308.5Zm-9.606-7.29h4.493l.527,1.419c.071.182.156.386.254.608a2.428,2.428,0,0,0,.273.512.986.986,0,0,0,.315.262.971.971,0,0,0,.454.1,1.05,1.05,0,0,0,.773-.327,1.025,1.025,0,0,0,.319-.723,3.3,3.3,0,0,0-.277-1.051l-.062-.161-2.889-7.313c-.119-.321-.228-.607-.335-.873a2.972,2.972,0,0,0-.323-.616,1.56,1.56,0,0,0-.5-.469,1.552,1.552,0,0,0-.781-.181,1.535,1.535,0,0,0-.773.181,1.475,1.475,0,0,0-.5.477,3.674,3.674,0,0,0-.362.739l-.239.627-.054.135-2.824,7.355c-.095.229-.179.46-.25.688a1.529,1.529,0,0,0-.073.477.978.978,0,0,0,.323.72,1.039,1.039,0,0,0,.746.315.838.838,0,0,0,.716-.3,4.676,4.676,0,0,0,.466-.985l.062-.165.527-1.449Zm3.747-1.5h-3.293l1.812-5.124,1.481,5.123Z"
                  transform="translate(-3327.144 15329)" />
              </svg>
            </span>
          </p>
          <div v-if="isShowAnswer34">
            <p>（2） 函数<i>y</i>=<i>f</i>（<i>x</i>）的图像如图3-24所示.</p>
            <p> <span class="zt-ls"><b>解</b></span>（2） 函数<i>y</i>=<i>f</i>（<i>x</i>）的图像如图3-24所示.</p>
            <p class="center"><img class="img-f" alt="" src="../../assets/images/0111-4.jpg" /></p>
            <p class="img">图3-24</p>
          </div>
          <iframe src="https://www.geogebra.org/calculator" frameborder="0" class="iframe-box"></iframe>
          <p class="p-btn" >
            <span>（3） 小李在返回A城途中，15：00刚好接到家人的电话，这时他距离A城多少千米？</span>
            <span class="btn-box" @click="isShowAnswer35 = !isShowAnswer35">
              <svg xmlns="http://www.w3.org/2000/svg" width="16.501" height="16.501" viewBox="0 0 20.501 20.501">
                <path class="a"
                  d="M3344.717-15308.5H3337.4a10.186,10.186,0,0,1-7.25-3,10.185,10.185,0,0,1-3-7.25A10.262,10.262,0,0,1,3337.4-15329a10.26,10.26,0,0,1,10.249,10.248,10.129,10.129,0,0,1-2.2,6.341v3.177A.734.734,0,0,1,3344.717-15308.5Zm-9.606-7.29h4.493l.527,1.419c.071.182.156.386.254.608a2.428,2.428,0,0,0,.273.512.986.986,0,0,0,.315.262.971.971,0,0,0,.454.1,1.05,1.05,0,0,0,.773-.327,1.025,1.025,0,0,0,.319-.723,3.3,3.3,0,0,0-.277-1.051l-.062-.161-2.889-7.313c-.119-.321-.228-.607-.335-.873a2.972,2.972,0,0,0-.323-.616,1.56,1.56,0,0,0-.5-.469,1.552,1.552,0,0,0-.781-.181,1.535,1.535,0,0,0-.773.181,1.475,1.475,0,0,0-.5.477,3.674,3.674,0,0,0-.362.739l-.239.627-.054.135-2.824,7.355c-.095.229-.179.46-.25.688a1.529,1.529,0,0,0-.073.477.978.978,0,0,0,.323.72,1.039,1.039,0,0,0,.746.315.838.838,0,0,0,.716-.3,4.676,4.676,0,0,0,.466-.985l.062-.165.527-1.449Zm3.747-1.5h-3.293l1.812-5.124,1.481,5.123Z"
                  transform="translate(-3327.144 15329)" />
              </svg>
            </span>
          </p>
          <div v-if="isShowAnswer35" >
            <p>（3） 小李从早晨8：00出发到15：00，共经过了7h，所以<i>x</i>=7，由（1） 中解析式得小李与<i>A</i>城的距离为</p>
            <p> <span class="zt-ls"><b>解</b></span>（3） 小李从早晨8：00出发到15：00，共经过了7h，所以<i>x</i>=7，由（1） 中解析式得小李与<i>A</i>城的距离为</p>
            <p class="center">-100×7+750=50（km）.</p>
            <p>所以，小李返回A城途中接到家人电话时，距离A城刚好50 km.</p>
          </div>
@@ -2572,30 +2575,6 @@
              </svg>
            </span>
          </p>
          <p class="p-btn">
            <span>
            （2） 该批发商不低于购入价进行销售，设该批发商每月销售这批绿色食品可获得利润为<i>w</i>元，用解析法表示函数<i>w</i>=<i>g</i>（<i>x</i>）；
            </span>
            <span class="btn-box" @click="isShowAnswer39 = !isShowAnswer39">
              <svg xmlns="http://www.w3.org/2000/svg" width="16.501" height="16.501" viewBox="0 0 20.501 20.501">
                <path class="a"
                  d="M3344.717-15308.5H3337.4a10.186,10.186,0,0,1-7.25-3,10.185,10.185,0,0,1-3-7.25A10.262,10.262,0,0,1,3337.4-15329a10.26,10.26,0,0,1,10.249,10.248,10.129,10.129,0,0,1-2.2,6.341v3.177A.734.734,0,0,1,3344.717-15308.5Zm-9.606-7.29h4.493l.527,1.419c.071.182.156.386.254.608a2.428,2.428,0,0,0,.273.512.986.986,0,0,0,.315.262.971.971,0,0,0,.454.1,1.05,1.05,0,0,0,.773-.327,1.025,1.025,0,0,0,.319-.723,3.3,3.3,0,0,0-.277-1.051l-.062-.161-2.889-7.313c-.119-.321-.228-.607-.335-.873a2.972,2.972,0,0,0-.323-.616,1.56,1.56,0,0,0-.5-.469,1.552,1.552,0,0,0-.781-.181,1.535,1.535,0,0,0-.773.181,1.475,1.475,0,0,0-.5.477,3.674,3.674,0,0,0-.362.739l-.239.627-.054.135-2.824,7.355c-.095.229-.179.46-.25.688a1.529,1.529,0,0,0-.073.477.978.978,0,0,0,.323.72,1.039,1.039,0,0,0,.746.315.838.838,0,0,0,.716-.3,4.676,4.676,0,0,0,.466-.985l.062-.165.527-1.449Zm3.747-1.5h-3.293l1.812-5.124,1.481,5.123Z"
                  transform="translate(-3327.144 15329)" />
              </svg>
            </span>
          </p>
          <p class="p-btn">
            <span>
            （3） 当销售单价为多少时，该批发商每月可获得最大利润？最大利润是多少？
            </span>
            <span class="btn-box" @click="isShowAnswer40 = !isShowAnswer40">
              <svg xmlns="http://www.w3.org/2000/svg" width="16.501" height="16.501" viewBox="0 0 20.501 20.501">
                <path class="a"
                  d="M3344.717-15308.5H3337.4a10.186,10.186,0,0,1-7.25-3,10.185,10.185,0,0,1-3-7.25A10.262,10.262,0,0,1,3337.4-15329a10.26,10.26,0,0,1,10.249,10.248,10.129,10.129,0,0,1-2.2,6.341v3.177A.734.734,0,0,1,3344.717-15308.5Zm-9.606-7.29h4.493l.527,1.419c.071.182.156.386.254.608a2.428,2.428,0,0,0,.273.512.986.986,0,0,0,.315.262.971.971,0,0,0,.454.1,1.05,1.05,0,0,0,.773-.327,1.025,1.025,0,0,0,.319-.723,3.3,3.3,0,0,0-.277-1.051l-.062-.161-2.889-7.313c-.119-.321-.228-.607-.335-.873a2.972,2.972,0,0,0-.323-.616,1.56,1.56,0,0,0-.5-.469,1.552,1.552,0,0,0-.781-.181,1.535,1.535,0,0,0-.773.181,1.475,1.475,0,0,0-.5.477,3.674,3.674,0,0,0-.362.739l-.239.627-.054.135-2.824,7.355c-.095.229-.179.46-.25.688a1.529,1.529,0,0,0-.073.477.978.978,0,0,0,.323.72,1.039,1.039,0,0,0,.746.315.838.838,0,0,0,.716-.3,4.676,4.676,0,0,0,.466-.985l.062-.165.527-1.449Zm3.747-1.5h-3.293l1.812-5.124,1.481,5.123Z"
                  transform="translate(-3327.144 15329)" />
              </svg>
            </span>
          </p>
          <div v-if="isShowAnswer38" > 
            <p><span class="zt-ls"><b>解</b></span>（1） 设函数<i>y</i>=<i>f</i>（<i>x</i>）的解析式是<i>y</i>=<i>kx</i>+<i>b</i>，则</p>
            <p><math display="0">
@@ -2660,15 +2639,39 @@
            <p>所以，函数<i>y</i>=<i>f</i>（<i>x</i>）的解析式可表示为</p>
            <p class="center"><i>y</i>=-20<i>x</i>+1 200，30≤<i>x</i>≤60.</p>
          </div>
          <p class="p-btn">
            <span>
            （2） 该批发商不低于购入价进行销售，设该批发商每月销售这批绿色食品可获得利润为<i>w</i>元，用解析法表示函数<i>w</i>=<i>g</i>（<i>x</i>）；
            </span>
            <span class="btn-box" @click="isShowAnswer39 = !isShowAnswer39">
              <svg xmlns="http://www.w3.org/2000/svg" width="16.501" height="16.501" viewBox="0 0 20.501 20.501">
                <path class="a"
                  d="M3344.717-15308.5H3337.4a10.186,10.186,0,0,1-7.25-3,10.185,10.185,0,0,1-3-7.25A10.262,10.262,0,0,1,3337.4-15329a10.26,10.26,0,0,1,10.249,10.248,10.129,10.129,0,0,1-2.2,6.341v3.177A.734.734,0,0,1,3344.717-15308.5Zm-9.606-7.29h4.493l.527,1.419c.071.182.156.386.254.608a2.428,2.428,0,0,0,.273.512.986.986,0,0,0,.315.262.971.971,0,0,0,.454.1,1.05,1.05,0,0,0,.773-.327,1.025,1.025,0,0,0,.319-.723,3.3,3.3,0,0,0-.277-1.051l-.062-.161-2.889-7.313c-.119-.321-.228-.607-.335-.873a2.972,2.972,0,0,0-.323-.616,1.56,1.56,0,0,0-.5-.469,1.552,1.552,0,0,0-.781-.181,1.535,1.535,0,0,0-.773.181,1.475,1.475,0,0,0-.5.477,3.674,3.674,0,0,0-.362.739l-.239.627-.054.135-2.824,7.355c-.095.229-.179.46-.25.688a1.529,1.529,0,0,0-.073.477.978.978,0,0,0,.323.72,1.039,1.039,0,0,0,.746.315.838.838,0,0,0,.716-.3,4.676,4.676,0,0,0,.466-.985l.062-.165.527-1.449Zm3.747-1.5h-3.293l1.812-5.124,1.481,5.123Z"
                  transform="translate(-3327.144 15329)" />
              </svg>
            </span>
          </p>
          <div v-if="isShowAnswer39" > 
            <p>（2） 由题意得，<i>w</i>=（<i>x</i>-30）<i>y</i></p>
            <p> <span class="zt-ls"><b>解</b></span>（2） 由题意得，<i>w</i>=（<i>x</i>-30）<i>y</i></p>
            <p>　　　　　　　　=（<i>x</i>-30）（-20<i>x</i>+1 200）</p>
            <p>　　　　　　　　=-20<i>x</i><sup>2</sup>+1 800<i>x</i>-36 000，</p>
            <p>所以，函数<i>w</i>=<i>g</i>（<i>x</i>）的解析式可表示为</p>
            <p class="center"><i>w</i>=-20<i>x</i><sup>2</sup>+1 800<i>x</i>-36 000，30≤<i>x</i>≤60.</p>
          </div>
          <p class="p-btn">
            <span>
            （3） 当销售单价为多少时，该批发商每月可获得最大利润？最大利润是多少？
            </span>
            <span class="btn-box" @click="isShowAnswer40 = !isShowAnswer40">
              <svg xmlns="http://www.w3.org/2000/svg" width="16.501" height="16.501" viewBox="0 0 20.501 20.501">
                <path class="a"
                  d="M3344.717-15308.5H3337.4a10.186,10.186,0,0,1-7.25-3,10.185,10.185,0,0,1-3-7.25A10.262,10.262,0,0,1,3337.4-15329a10.26,10.26,0,0,1,10.249,10.248,10.129,10.129,0,0,1-2.2,6.341v3.177A.734.734,0,0,1,3344.717-15308.5Zm-9.606-7.29h4.493l.527,1.419c.071.182.156.386.254.608a2.428,2.428,0,0,0,.273.512.986.986,0,0,0,.315.262.971.971,0,0,0,.454.1,1.05,1.05,0,0,0,.773-.327,1.025,1.025,0,0,0,.319-.723,3.3,3.3,0,0,0-.277-1.051l-.062-.161-2.889-7.313c-.119-.321-.228-.607-.335-.873a2.972,2.972,0,0,0-.323-.616,1.56,1.56,0,0,0-.5-.469,1.552,1.552,0,0,0-.781-.181,1.535,1.535,0,0,0-.773.181,1.475,1.475,0,0,0-.5.477,3.674,3.674,0,0,0-.362.739l-.239.627-.054.135-2.824,7.355c-.095.229-.179.46-.25.688a1.529,1.529,0,0,0-.073.477.978.978,0,0,0,.323.72,1.039,1.039,0,0,0,.746.315.838.838,0,0,0,.716-.3,4.676,4.676,0,0,0,.466-.985l.062-.165.527-1.449Zm3.747-1.5h-3.293l1.812-5.124,1.481,5.123Z"
                  transform="translate(-3327.144 15329)" />
              </svg>
            </span>
          </p>
          <div v-if="isShowAnswer40" > 
            <p>（3） 由（2） 知，<i>w</i>=-20<i>x</i><sup>2</sup>+1 800<i>x</i>-36 000，30≤<i>x</i>≤60，配方得</p>
            <p> <span class="zt-ls"><b>解</b></span>（3） 由（2） 知，<i>w</i>=-20<i>x</i><sup>2</sup>+1 800<i>x</i>-36 000，30≤<i>x</i>≤60，配方得</p>
            <p class="center"><i>w</i>=-20（<i>x</i>-45）<sup>2</sup>+4 500.</p>
            <p>所以，当<i>x</i>=45时，<i>w</i>的值最大，最大值是4 500.</p>
            <p>答：当销售单价为45元时，该批发商每月可获得最大利润，最大利润是4 500元.</p>
@@ -2826,7 +2829,7 @@
    <!-- 112 -->
    <div class="page-box hidePage" page="119">
    </div>
        <!-- 函数控件弹窗 -->
    <!-- 函数控件弹窗 -->
    <el-dialog :visible.sync="dialogVisible" width="60%" :append-to-body="true" :show-close="false">
      <div slot="title" style="padding: 0 0 15px 0;position: relative;">
        <svg style="position: absolute; right:10px;cursor: pointer;" @click="dialogVisible = false" t="1718596022986"