2024年成考专升本《高等数学一》每日一练试题05月17日

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05/17
<p class="introTit">单选题</p><p>1、下列函数在[1,e]上满足拉格朗日中值定理条件的是()。</p><ul><li>A:1/(1-x)</li><li>B:lnx</li><li>C:1/(1-lnx)</li><li>D:<img src='https://img2.meite.com/questions/202211/296385d30cd094d.png' /></li></ul><p>答 案:B</p><p>解 析:AC两项,在[1,e]不连续,在端点处存在间断点(无穷间断点);B项,lnx在[1,e]上有定义,所以在[1,e]上连续,且<img src="https://img2.meite.com/questions/202211/296385d3292f64f.png" />在(1,e)内有意义,所以lnx在(1,e)内可导;D项,定义域为[2,+∞],在[1,2)上无意义。</p><p>2、设方程<img src="https://img2.meite.com/questions/202303/1764141ad6c0667.png" />有特解<img src="https://img2.meite.com/questions/202303/1764141ae22509f.png" />则他的通解是()</p><ul><li>A:<img src='https://img2.meite.com/questions/202303/1764141b0642a0e.png' /></li><li>B:<img src='https://img2.meite.com/questions/202303/1764141af755d92.png' /></li><li>C:<img src='https://img2.meite.com/questions/202303/1764141afe6b1c1.png' /></li><li>D:<img src='https://img2.meite.com/questions/202303/1764141af294f2a.png' /></li></ul><p>答 案:A</p><p>解 析:考虑对应的齐次方程<img src="https://img2.meite.com/questions/202303/1764141b2424195.png" />的通解,特征方程<img src="https://img2.meite.com/questions/202303/1764141b3457f4b.png" />所以r1=-1,r2=3,所以<img src="https://img2.meite.com/questions/202303/1764141b6110c7c.png" />的通解为<img src="https://img2.meite.com/questions/202303/1764141b699a2d7.png" />,所以原方程的通解为<img src="https://img2.meite.com/questions/202303/1764141b8adaae9.png" /></p><p>3、设y=f(x)在点x<sub>0</sub>=0处可导,且x<sub>0</sub>=0为f(x)的极值点,则()。</p><ul><li>A:f'(0)=0</li><li>B:f(0)=0</li><li>C:f(0)=1</li><li>D:f(0)不可能是0</li></ul><p>答 案:A</p><p>解 析:f(x)在x=0处为极值点,不妨设为极大值点。又f(x)在x=0处可导,则有<img src="https://img2.meite.com/questions/202211/296385c6c211026.png" />,<img src="https://img2.meite.com/questions/202211/296385c6d96bb6b.png" />,则有<img src="https://img2.meite.com/questions/202211/296385c6e4d7886.png" />,<img src="https://img2.meite.com/questions/202211/296385c6f25fb2c.png" />异号,又f(x)在x=0处可导,所以<img src="https://img2.meite.com/questions/202211/296385c70eed20d.png" />。</p><p class="introTit">主观题</p><p>1、设有一圆形薄片<img src="https://img2.meite.com/questions/202212/016388539282716.png" />,在其上一点M(x,y)的面密度与点M到点(0,0)的距离成正比,求分布在此薄片上的物质的质量。</p><p>答 案:解:设密度为<img src="https://img2.meite.com/questions/202212/01638853a97290f.png" />故质量<img src="https://img2.meite.com/questions/202212/01638853c0a4ea0.png" /><img src="https://img2.meite.com/questions/202212/01638853e14485a.png" /></p><p>2、求<img src="https://img2.meite.com/questions/202212/03638af06c97e45.png" />的极值.</p><p>答 案:解:<img src="https://img2.meite.com/questions/202212/03638af07e60777.png" />,<img src="https://img2.meite.com/questions/202212/03638af08e40724.png" />故由<img src="https://img2.meite.com/questions/202212/03638af09f241ac.png" />得驻点(1/2,-1),<img src="https://img2.meite.com/questions/202212/03638af0ba9085a.png" />于是<img src="https://img2.meite.com/questions/202212/03638af0cf74916.png" />,且<img src="https://img2.meite.com/questions/202212/03638af0ec8e584.png" />。故(1/2,-1)为极小值点,且极小值为<img src="https://img2.meite.com/questions/202212/03638af0fec78e2.png" /></p><p>3、设<img src="https://img2.meite.com/questions/202212/03638aff4f737d0.png" />存在且<img src="https://img2.meite.com/questions/202212/03638aff59d37e0.png" />,求<img src="https://img2.meite.com/questions/202212/03638aff6554eac.png" /></p><p>答 案:解:设<img src="https://img2.meite.com/questions/202212/03638aff7078ded.png" />对<img src="https://img2.meite.com/questions/202212/03638aff830ad7a.png" />两边同时求极限,得<img src="https://img2.meite.com/questions/202212/03638affa03127b.png" />,即<img src="https://img2.meite.com/questions/202212/03638affaad78d4.png" />,得<img src="https://img2.meite.com/questions/202212/03638affb8a0ed1.png" />。</p><p class="introTit">填空题</p><p>1、设区域D<img src="https://img2.meite.com/questions/202303/176414267154ab7.png" /><img src="https://img2.meite.com/questions/202303/1764142676bbd24.png" />()  </p><p>答 案:2</p><p>解 析:<img src="https://img2.meite.com/questions/202303/17641426898be6e.png" /></p><p>2、设<img src="https://img2.meite.com/questions/202211/176375a235be9a3.png" />,则<img src="https://img2.meite.com/questions/202211/176375a2449fce9.png" />()。</p><p>答 案:2e<sup>2</sup></p><p>解 析:<img src="https://img2.meite.com/questions/202211/176375a2610bc67.png" />,则<img src="https://img2.meite.com/questions/202211/176375a26dd4a8b.png" /></p><p>3、幂级数<img src="https://img2.meite.com/questions/202212/0163885c51c8bb3.png" />的收敛半径为()。</p><p>答 案:1</p><p>解 析:<img src="https://img2.meite.com/questions/202212/0163885c5fa0d30.png" />是最基本的幂级数之一,a<sub>n</sub>=1,<img src="https://img2.meite.com/questions/202212/0163885c84c560b.png" />,故收敛半径为1。</p><p class="introTit">简答题</p><p>1、函数y=y(x)由方程<img src="https://img2.meite.com/questions/202303/17641407dc7401a.png" />确定,求dy</p><p>答 案:<img src="https://img2.meite.com/questions/202303/176414080f37d43.png" /></p>
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