2024年成考高起点《数学(理)》每日一练试题08月08日
<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、已知点M(1,2),N(2,3),则直线MN的斜率为()。</p><ul><li>A:<img src='https://img2.meite.com/questions/202404/1966222d578699e.png' /></li><li>B:1</li><li>C:<img src='https://img2.meite.com/questions/202404/1966222d5cbf82d.png' /></li><li>D:-1</li></ul><p>答 案:B</p><p>解 析:本题主要考查的知识点为直线的斜率.
直线MN的斜率为:<img src="https://img2.meite.com/questions/202404/1966222d6b403b0.png" /></p><p>3、若x<y<0,则()。
</p><ul><li>A:<img src='https://img2.meite.com/questions/202404/1966222cf6e9ee9.png' /></li><li>B:<img src='https://img2.meite.com/questions/202404/1966222d006070f.png' /></li><li>C:<img src='https://img2.meite.com/questions/202404/1966222d0861b3e.png' /></li><li>D:<img src='https://img2.meite.com/questions/202404/1966222d1149cd7.png' /></li></ul><p>答 案:D.</p><p>解 析:本题主要考查的知识点为不等式的性质.
因为x<y<0,故<img src="https://img2.meite.com/questions/202404/1966222d1f86e43.png" /></p><p>4、设α是第三象限角,若<img src="https://img2.meite.com/questions/202303/15641164a2250e5.png" />,则sinα=()</p><ul><li>A:<img src='https://img2.meite.com/questions/202303/1564116483e2d49.png' /></li><li>B:<img src='https://img2.meite.com/questions/202303/156411648920e99.png' /></li><li>C:<img src='https://img2.meite.com/questions/202303/156411648dc7387.png' /></li><li>D:<img src='https://img2.meite.com/questions/202303/156411649179a9b.png' /></li></ul><p>答 案:D</p><p>解 析:由于<img src="https://img2.meite.com/questions/202303/1564116825627fd.png" />,而α为第三象限角,故<img src="https://img2.meite.com/questions/202303/156411684ec6fe9.png" /></p><p class="introTit">主观题</p><p>1、已知函数f(x)=(x-4)(x<sup>2</sup>-a)
(I)求f"(x);
(Ⅱ)若f"(-1)=8,求f(x)在区间[0,4]的最大值与最小值</p><p>答 案:<img src="https://img2.meite.com/questions/202404/1966222f3f733cc.png" /><img src="https://img2.meite.com/questions/202404/1966222f47c8e62.png" /></p><p>2、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>3、已知抛物线C:y<sup>2</sup>=2px(p>0)的焦点到准线的距离为1。
(I)求C的方程;
(Ⅱ)若A(1,m)(m>0)为C上一点,O为坐标原点,求C上另一点B的坐标,使得OA⊥OB</p><p>答 案:(I)由题意,该抛物线的焦点到准线的距离为<img src="https://img2.meite.com/questions/202404/1966222edee972e.png" />
所以抛物线C的方程为<img src="https://img2.meite.com/questions/202404/1966222ee6c66f9.png" />
(Ⅱ)因A(l,m)(m>0)为C上一点,故有m<sup>2</sup>=2,
可得<img src="https://img2.meite.com/questions/202404/1966222ef5c5007.png" />因此A点坐标为<img src="https://img2.meite.com/questions/202404/1966222efb949fc.png" />
设B点坐标为<img src="https://img2.meite.com/questions/202404/1966222f0a5cbbb.png" />则<img src="https://img2.meite.com/questions/202404/1966222f11e9340.png" />
因为<img src="https://img2.meite.com/questions/202404/1966222f17c1b05.png" />则有<img src="https://img2.meite.com/questions/202404/1966222f1dce70a.png" />
即<img src="https://img2.meite.com/questions/202404/1966222f27533ea.png" />解得x0=4
所以B点的坐标为<img src="https://img2.meite.com/questions/202404/1966222f308351e.png" />
</p><p>4、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 class="introTit">填空题</p><p>1、不等式<img src="https://img2.meite.com/questions/202303/28642289d6ca884.png" />的解集为()
</p><p>答 案:<img src="https://img2.meite.com/questions/202303/28642289e5c9bcc.png" /></p><p>解 析:<img src="https://img2.meite.com/questions/202303/28642289efc4ba4.png" /><img src="https://img2.meite.com/questions/202303/28642289fa37c87.png" /><img src="https://img2.meite.com/questions/202303/2864228a0077853.png" /></p><p>2、九个学生期末考试的成绩分别为79 63 88 94 99 77 89 81 85这九个学生成绩的中位数为______。
</p><p>答 案:85
</p><p>解 析:本题主要考查的知识点为中位数. 将成绩按由小到大排列:63,77,79,81,85,88,89,94,99.因此中位数为85。</p>