2024年成考高起点《数学(理)》每日一练试题02月09日

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02/09
<p class="introTit">单选题</p><p>1、(2-3i)<sup>2</sup>=()</p><ul><li>A:13-6i</li><li>B:13-12i</li><li>C:-5-6i</li><li>D:-5-12i</li></ul><p>答 案:D</p><p>解 析:<img src="https://img2.meite.com/questions/202303/15641169af99ac7.png" /></p><p>2、设集合M={x||x-2|<1},N={x|x>2},则M∩N=()</p><ul><li>A:{x|1<x<3}</li><li>B:{x|x>2}</li><li>C:{x|2<x<3}</li><li>D:{x|1<x<2}</li></ul><p>答 案:C</p><p>解 析:M={x||x-2|<1}解得{x|-1<x-2<1}={x|1<x<3},故M∩N={x|2<x<3}</p><p>3、中心在坐标原点,对称轴为坐标轴,且一个顶点(3,0),虚轴长为8的双曲线方程是()</p><ul><li>A:<img src='https://img2.meite.com/questions/202303/15641165746df3c.png' /></li><li>B:<img src='https://img2.meite.com/questions/202303/1564116579ce1fd.png' /></li><li>C:<img src='https://img2.meite.com/questions/202303/156411657f3914e.png' /></li><li>D:<img src='https://img2.meite.com/questions/202303/1564116582cc298.png' /></li></ul><p>答 案:B</p><p>解 析:双曲线有一个顶点为(3,0),因此所求双曲线的实轴在x轴上,可排除A、C选项,又由于虚轴长为8,故b=4,即b<sup>2</sup>=16,故双曲线方程为<img src="https://img2.meite.com/questions/202303/15641169fee41e2.png" /></p><p>4、对满足a>b的任意两个非零实数,下列不等式成立的是()  </p><ul><li>A:<img src='https://img2.meite.com/questions/202303/2864228b1f8efca.png' /></li><li>B:<img src='https://img2.meite.com/questions/202303/2864228b2567c86.png' /></li><li>C:<img src='https://img2.meite.com/questions/202303/2864228b2a86110.png' /></li><li>D:<img src='https://img2.meite.com/questions/202303/2864228b30e50d4.png' /></li></ul><p>答 案:D</p><p>解 析:A错误,例如-2>4,而<img src="https://img2.meite.com/questions/202303/2864228ba68a732.png" /> B错误,例如:-10>100,而<img src="https://img2.meite.com/questions/202303/2864228bbe163a2.png" /> C错误,例如:-1>-2,而<img src="https://img2.meite.com/questions/202303/2864228bd9de925.png" /> <img src="https://img2.meite.com/questions/202303/2864228be175c60.png" /></p><p class="introTit">主观题</p><p>1、在正四棱柱ABCD-A'B'C'D'中,<img src="https://img2.meite.com/questions/202303/2864229a3bc3098.png" /> (Ⅰ)写出向量<img src="https://img2.meite.com/questions/202303/2864229a57ba174.png" />和<img src="https://img2.meite.com/questions/202303/2864229a5e46ac8.png" />关于基底{a,b,c}的分解式; (Ⅱ)求证:<img src="https://img2.meite.com/questions/202303/2864229a76ba56d.png" /> (Ⅲ)求证:<img src="https://img2.meite.com/questions/202303/2864229a7fdd541.png" />  </p><p>答 案:(Ⅰ)由题意知(如图所示) <img src="https://img2.meite.com/questions/202303/2864229af6b1567.png" /> <img src="https://img2.meite.com/questions/202303/2864229afe90f50.png" /> <img src="https://img2.meite.com/questions/202303/2864229b08314c5.png" />  </p><p>2、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>3、已知数列<img src="https://img2.meite.com/questions/202303/286422511c19556.png" />的前n项和<img src="https://img2.meite.com/questions/202303/2864225128dc6e0.png" /> 求证:<img src="https://img2.meite.com/questions/202303/286422513318bbb.png" />是等差数列,并求公差和首项。  </p><p>答 案:<img src="https://img2.meite.com/questions/202303/286422514f41b7b.png" /> <img src="https://img2.meite.com/questions/202303/28642251563e39b.png" />  </p><p>4、在△ABC中,B=120°,BC=4,△ABC的面积为<img src="https://img2.meite.com/questions/202303/15641165ec55404.png" />,求AC.</p><p>答 案:由△ABC的面积为<img src="https://img2.meite.com/questions/202303/15641165ec55404.png" />得<img src="https://img2.meite.com/questions/202303/1564116bba3c98d.png" />所以AB =4.因此<img src="https://img2.meite.com/questions/202303/1564116be4bebd5.png" />所以<img src="https://img2.meite.com/questions/202303/1564116be967e8f.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、若平面向量a=(x,1),b=(1,-2),且a//b,则x=()  </p><p>答 案:<img src="https://img2.meite.com/questions/202303/286422508f0554f.png" /></p><p>解 析:由于a//b,故<img src="https://img2.meite.com/questions/202303/286422509cd5c14.png" /></p>
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