2024年成考高起点《数学(理)》每日一练试题06月02日
<p class="introTit">单选题</p><p>1、设f(x)=x<sup>3</sup>+ax<sup>2</sup>+x为奇函数,则a=()。</p><ul><li>A:1</li><li>B:0</li><li>C:</li><li>D:-2
D.C.-1
</li></ul><p>答 案:B</p><p>解 析:本题主要考查的知识点为函数的奇偶性.
因为f(x)为奇函数,故f(-x)=-f(x)。即-x<sup>3</sup>+ax<sup>2</sup>-x=-x<sup>3</sup>-ax<sup>2</sup>-x,a=0。</p><p>2、下列函数中,为奇函数的是()</p><ul><li>A:<img src='https://img2.meite.com/questions/202303/156411642c7ba59.png' /></li><li>B:<img src='https://img2.meite.com/questions/202303/156411643238049.png' /></li><li>C:<img src='https://img2.meite.com/questions/202303/1564116437cc5f5.png' /></li><li>D:<img src='https://img2.meite.com/questions/202303/156411643c1ff56.png' /></li></ul><p>答 案:B</p><p>解 析:当f(-x)=-f(x),函数f(x)是奇函数,只有选项B符合.</p><p>3、函数<img src="https://img2.meite.com/questions/202303/15641164b43c663.png" />的反函数是()</p><ul><li>A:<img src='https://img2.meite.com/questions/202303/15641164d78e1fc.png' /></li><li>B:<img src='https://img2.meite.com/questions/202303/15641164de92884.png' /></li><li>C:<img src='https://img2.meite.com/questions/202303/15641164e5206d4.png' /></li><li>D:<img src='https://img2.meite.com/questions/202303/15641164e93e32e.png' /></li></ul><p>答 案:A</p><p>解 析:<img src="https://img2.meite.com/questions/202303/15641168660282b.png" />,由于x≤0,故<img src="https://img2.meite.com/questions/202303/1564116881a60a4.png" />把x与y互换,得所求反函数为<img src="https://img2.meite.com/questions/202303/15641168ab18774.png" /></p><p>4、一批产品共有5件,其中4件为正品,1件为次品,从中一次取出2件均为正品的概率为()。
</p><ul><li>A:0.6</li><li>B:0.5</li><li>C:0.4</li><li>D:0.3</li></ul><p>答 案:A</p><p>解 析:本题主要考查的知识点为随机事件的概率
一次取出2件均为正品的概率为<img src="https://img2.meite.com/questions/202404/1966222cd8d5e51.png" />
</p><p class="introTit">主观题</p><p>1、已知等差数列前n项和<img src="https://img2.meite.com/questions/202303/2864228a3204a03.png" />
(Ⅰ)求这个数列的通项公式;(Ⅱ)求数列第六项到第十项的和</p><p>答 案:<img src="https://img2.meite.com/questions/202303/2864228a568855e.png" /> <img src="https://img2.meite.com/questions/202303/2864228a63bc5a4.png" />
</p><p>2、记△ABC的内角A,B,C的对边分别为a,b,c,已知B=60°,b<sup>2</sup>=ac,求A。
</p><p>答 案:由余弦定理b<sup>2</sup>=a<sup>2</sup>+c<sup>2</sup>-2accosB,可得ac=a<sup>2</sup>+c<sup>2</sup>-ac,即a<sup>2</sup>+c<sup>2</sup>-2ac=(a-c)<sup>2</sup>=0,解得a=c。
又因为B=60°,故△ABC为等边三角形,所以A=60°</p><p>3、已知等差数列{an}中,a1+a2+a3=6,a2+a4+a5= 12求{an}的首项与公差。
</p><p>答 案:因为{an}为等差数列,<img src="https://img2.meite.com/questions/202404/1966222ec336fd9.png" /><img src="https://img2.meite.com/questions/202404/1966222ec71ecf8.png" /></p><p>4、已知直线l的斜率为1,l过抛物线C:<img src="https://img2.meite.com/questions/202303/156411660ae04fb.png" />的焦点,且与C交于A,B两点.(I)求l与C的准线的交点坐标;<br />(II)求|AB|.</p><p>答 案:(I)C的焦点为<img src="https://img2.meite.com/questions/202303/1564116c40cf40a.png" />,准线为<img src="https://img2.meite.com/questions/202303/1564116c45024f5.png" />由题意得l的方程为<img src="https://img2.meite.com/questions/202303/1564116c5cf0409.png" />因此l与C的准线的交点坐标为<img src="https://img2.meite.com/questions/202303/1564116c7901a26.png" />(II)由<img src="https://img2.meite.com/questions/202303/1564116c9294ce9.png" />,得<img src="https://img2.meite.com/questions/202303/1564116c9d411f3.png" />设A(x1,y1),B(x2,y2),则<img src="https://img2.meite.com/questions/202303/1564116cd0bfaf7.png" />因此<img src="https://img2.meite.com/questions/202303/1564116ce1375a9.png" /></p><p class="introTit">填空题</p><p>1、函数<img src="https://img2.meite.com/questions/202303/28642285dd68e2c.png" />的定义域是()</p><p>答 案:<img src="https://img2.meite.com/questions/202303/28642285f367786.png" /></p><p>解 析:<img src="https://img2.meite.com/questions/202303/28642285fcec513.png" /><img src="https://img2.meite.com/questions/202303/2864228601aa2da.png" />所以函数<img src="https://img2.meite.com/questions/202303/286422860d8135c.png" />的定义域是<img src="https://img2.meite.com/questions/202303/286422861644b62.png" /></p><p>2、过点(2,0)作圆x2+y2=1的切线,切点的横坐标为()。</p><p>答 案:<img src="https://img2.meite.com/questions/202404/20662380f056b37.png" /></p><p>解 析:本题主要考查的知识点为圆的切线.
设切点(x0,y0)则有<img src="https://img2.meite.com/questions/202404/20662380f985f55.png" />
即<img src="https://img2.meite.com/questions/202404/20662381033a418.png" /><img src="https://img2.meite.com/questions/202404/206623810c425f9.png" />所以<img src="https://img2.meite.com/questions/202404/2066238119981c7.png" />故切点横坐标为<img src="https://img2.meite.com/questions/202404/206623812263a88.png" />
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