2024年成考高起点《数学(理)》每日一练试题03月11日
聚题库
03/11
<p class="introTit">单选题</p><p>1、<img src="https://img2.meite.com/questions/202303/2864225b891ad2c.png" />展开式中,末3项的系数(a,x 均未知) 之和为()
</p><ul><li>A：22</li><li>B：12</li><li>C：10</li><li>D：-10</li></ul><p>答 案：C</p><p>解 析：<img src="https://img2.meite.com/questions/202303/2864225bbb4b976.png" /><img src="https://img2.meite.com/questions/202303/2864225bc299c02.png" /><img src="https://img2.meite.com/questions/202303/2864225bcaa8096.png" />末三项数之和为<img src="https://img2.meite.com/questions/202303/2864225bdfc7788.png" /><img src="https://img2.meite.com/questions/202303/2864225beaa0cc1.png" /></p><p>2、将一颗骰子抛掷1次,到的点数为偶数的概率为
</p><ul><li>A：<img src='https://img2.meite.com/questions/202303/28642253b027cee.png' /></li><li>B：<img src='https://img2.meite.com/questions/202303/28642253b3b5865.png' /></li><li>C：<img src='https://img2.meite.com/questions/202303/28642253beb605d.png' /></li><li>D：<img src='https://img2.meite.com/questions/202303/28642253b9ec882.png' /></li></ul><p>答 案：D</p><p>解 析：一颗骰子的点数分别为1,2,3,4,5,6,其中偶数与奇数各占一半,故抛掷1次,得到的点数为偶数的概率为<img src="https://img2.meite.com/questions/202303/286422545e57429.png" /></p><p>3、已知复数z=a+bi,其中a,<img src="https://img2.meite.com/questions/202303/2864224cfda7e7d.png" />且b≠0，则（）
</p><ul><li>A：<img src='https://img2.meite.com/questions/202303/2864224d5102575.png' /></li><li>B：<img src='https://img2.meite.com/questions/202303/2864224d5d6afe7.png' /></li><li>C：<img src='https://img2.meite.com/questions/202303/2864224d6343bc7.png' /></li><li>D：<img src='https://img2.meite.com/questions/202303/2864224d6ad6d12.png' /></li></ul><p>答 案：C</p><p>解 析：注意区分<img src="https://img2.meite.com/questions/202303/2864224f432bb09.png" /> <img src="https://img2.meite.com/questions/202303/2864224f5bec577.png" />
</p><p>4、（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 class="introTit">主观题</p><p>1、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>2、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>3、为了测河的宽,在岸边选定两点A和B,望对岸标记物C,测得<img src="https://img2.meite.com/questions/202303/2864228db8c0e49.png" />AB=120m,求河的宽
<img src="https://img2.meite.com/questions/202303/2864228dd64bdcb.png" /></p><p>答 案：如图， <img src="https://img2.meite.com/questions/202303/2864228df3f06d3.png" />
∵∠C=180°-30°-75°=75°
∴△ABC为等腰三角形，则AC=AB=120m
过C做CD⊥AB,则由Rt△ACD可求得CD=<img src="https://img2.meite.com/questions/202303/2864228e8a387f3.png" />=60m，
即河宽为60m
</p><p>4、设函数f(x)=<img src="https://img2.meite.com/questions/202303/28642286431b211.png" />
(Ⅰ)求f(x)的单调区间;
(Ⅱ)求 f(x)的极值</p><p>答 案：(Ⅰ)函数的定义域为<img src="https://img2.meite.com/questions/202303/28642286bee9cc3.png" /> <img src="https://img2.meite.com/questions/202303/28642286c7d68a9.png" />
(Ⅱ)<img src="https://img2.meite.com/questions/202303/28642286d3444c8.png" />
</p><p class="introTit">填空题</p><p>1、<img src="https://img2.meite.com/questions/202303/2864228ce0438da.png" />的展开式是（）</p><p>答 案：<img src="https://img2.meite.com/questions/202303/2864228d0c480eb.png" /></p><p>解 析：<img src="https://img2.meite.com/questions/202303/2864228d4197eb2.png" /><img src="https://img2.meite.com/questions/202303/2864228d47da120.png" /><img src="https://img2.meite.com/questions/202303/2864228d5101aa0.png" /><img src="https://img2.meite.com/questions/202303/2864228d5bc2a57.png" /><img src="https://img2.meite.com/questions/202303/2864228d65510b6.png" /></p><p>2、长方体的长、宽、高分别为2,3,6，则该长方体的对角线长为（）</p><p>答 案：7</p><p>解 析：由题可知长方体的底面的对角线长为<img src="https://img2.meite.com/questions/202303/1564116b1132166.png" />，则在由高、底面对角线、长方体的对角线组成的三角形中，长方体的对角线长为<img src="https://img2.meite.com/questions/202303/1564116b3811959.png" /></p>
