2024年成考专升本《高等数学二》每日一练试题06月14日
<p class="introTit">判断题</p><p>1、若<img src="https://img2.meite.com/questions/202307/1364af5780970e6.png" />,则<img src="https://img2.meite.com/questions/202307/1364af578624075.png" />。()
</p><p>答 案:错</p><p>解 析:<img src="https://img2.meite.com/questions/202212/06638ef8852e1bd.png" />所以<img src="https://img2.meite.com/questions/202212/06638ef88b66bc1.png" /> </p><p class="introTit">单选题</p><p>1、<img src="https://img2.meite.com/questions/202212/0763900d56bb6b1.png" />()</p><ul><li>A:<img src='https://img2.meite.com/questions/202212/0763900d6874b3b.png' /></li><li>B:<img src='https://img2.meite.com/questions/202212/0763900d734524d.png' /></li><li>C:<img src='https://img2.meite.com/questions/202212/0763900d7f21c24.png' /></li><li>D:<img src='https://img2.meite.com/questions/202212/0763900d892933a.png' /></li></ul><p>答 案:C</p><p>解 析:<img src="https://img2.meite.com/questions/202212/0763900d9c64dc3.png" /></p><p>2、设y=f(x)在点x处的切线斜率为<img src="https://img2.meite.com/questions/202212/0763900db7ddf62.png" />,则过点(0,1)的曲线方程为()</p><ul><li>A:<img src='https://img2.meite.com/questions/202212/0763900dc56fcc0.png' /></li><li>B:<img src='https://img2.meite.com/questions/202212/0763900dce6b81a.png' /></li><li>C:<img src='https://img2.meite.com/questions/202212/0763900dd9002cc.png' /></li><li>D:<img src='https://img2.meite.com/questions/202212/0763900de3586cd.png' /></li></ul><p>答 案:A</p><p>解 析:<img src="https://img2.meite.com/questions/202212/0763900df04452d.png" />过点(0,1)得C=2,所以<img src="https://img2.meite.com/questions/202212/0763900dfe7cad7.png" /></p><p class="introTit">主观题</p><p>1、某射手击中10环的概率为0.26,击中9环的概率为0.32,击中8环的概率为0.36,求在一次射击中不低于8环的概率.</p><p>答 案:解:设A={击中10环),B={击中9环),C={击中8环),D={击中不低于8环),则D=A+B+C,由于A,B,C相互独立,所以P(D)=P(A+B+C)=P(A)+P(B)+P(C)=0.26+0.32+0.36=0.94</p><p>2、计算<img src="https://img2.meite.com/questions/202212/076390384865398.png" />.</p><p>答 案:解:<img src="https://img2.meite.com/questions/202212/076390385942f20.png" /></p><p class="introTit">填空题</p><p>1、若f(x)在x=a处可导,则<img src="https://img2.meite.com/questions/202212/07638ff37e835dc.png" />=().</p><p>答 案:8f'(a)</p><p>解 析:因为f(x)在x=a处可导,<img src="https://img2.meite.com/questions/202212/07638ff3a16e245.png" /></p><p>2、设y=sinx,则<img src="https://img2.meite.com/questions/202303/21641914679182e.png" />=()
</p><p>答 案:-sinx</p><p>解 析:由y=sinx,且<img src="https://img2.meite.com/questions/202303/21641914a1d12f4.png" />则<img src="https://img2.meite.com/questions/202303/21641914b136fb6.png" />=sin(5π+x)=sin(π+x)=-sinx</p><p class="introTit">简答题</p><p>1、<img src="https://img2.meite.com/questions/202404/22662627d8bd5d8.png" />
</p><p>答 案:<img src="https://img2.meite.com/questions/202404/22662627e11b236.png" /></p><p>2、已知函数f(x)=ax<sup>3</sup>-bx<sup>2</sup>+cx在区间<img src="https://img2.meite.com/questions/202212/07639002a0c63f6.png" />内是奇函数,且当x=1时,f(x)有极小值<img src="https://img2.meite.com/questions/202212/07639002ba72fe4.png" />,求另一个极值及此曲线的拐点.
</p><p>答 案:f(x)=ax<sup>3</sup>-bx<sup>2</sup>+cx,<img src="https://img2.meite.com/questions/202212/07639002da708ed.png" /> 由于f(x)是奇函数,则必有x<sup>2</sup>的系数为0,即b=0.
<img src="https://img2.meite.com/questions/202212/07639003148fbf6.png" />即a+c=<img src="https://img2.meite.com/questions/202212/076390032089cb2.png" />,<img src="https://img2.meite.com/questions/202212/0763900324b36b3.png" />得3a+c=0.解得a=<img src="https://img2.meite.com/questions/202212/076390033fe0499.png" />c=<img src="https://img2.meite.com/questions/202212/0763900347cfddd.png" />
此时<img src="https://img2.meite.com/questions/202212/07639003591bd3b.png" />
令<img src="https://img2.meite.com/questions/202212/0763900361d0796.png" />得<img src="https://img2.meite.com/questions/202212/07639003674342f.png" /><img src="https://img2.meite.com/questions/202212/076390036dd8f49.png" />所以<img src="https://img2.meite.com/questions/202212/076390037794ea3.png" />为极大值,<img src="https://img2.meite.com/questions/202212/07639003826209a.png" />得x=0,x<0时,<img src="https://img2.meite.com/questions/202212/0763900396d70f8.png" />
所以(0,0)为曲线的拐点.</p>