2024年成考高起点《数学(文史)》每日一练试题02月24日
<p class="introTit">单选题</p><p>1、不等式|2x-3|≤1的解集为()</p><ul><li>A:{x|1≤x≤2}</li><li>B:{x|x≤-1或x≥2}</li><li>C:{x|1≤x≤3}</li><li>D:{x|2≤x≤3}</li></ul><p>答 案:A</p><p>解 析:<img src="https://img2.meite.com/questions/202303/2964239aeb5ea0d.png" /><img src="https://img2.meite.com/questions/202303/2964239afad8c35.png" />故原不等式的解集为{x|1≤x≤2}</p><p>2、函数<img src="https://img2.meite.com/questions/202303/296423e9f4c42ba.png" />与y<img src="https://img2.meite.com/questions/202303/296423e9fce2f9b.png" />的图像之间的关系是
</p><ul><li>A:关于原点对称</li><li>B:关于x轴对称</li><li>C:关于直线 y=1对称</li><li>D:关于y轴对称</li></ul><p>答 案:D</p><p>解 析:<img src="https://img2.meite.com/questions/202303/296423ea4eab0e4.png" /><img src="https://img2.meite.com/questions/202303/296423ea5d59f26.png" />关于y轴对称,</p><p>3、已知向量i,j为互相垂直的单位向量,向量a=2i+mj,若|a|=2,则m=()</p><ul><li>A:-2</li><li>B:-1</li><li>C:0</li><li>D:1</li></ul><p>答 案:C</p><p>解 析:由题可知a=(2,m),因此<img src="https://img2.meite.com/questions/202303/1464102be29a7c0.png" />,故m=0.</p><p>4、设α是三角形的一个内角,若<img src="https://img2.meite.com/questions/202303/1464102637baabc.png" />,则sinα=()</p><ul><li>A:<img src='https://img2.meite.com/questions/202303/146410277c73796.png' /></li><li>B:<img src='https://img2.meite.com/questions/202303/14641027838231f.png' /></li><li>C:<img src='https://img2.meite.com/questions/202303/1464102788b3139.png' /></li><li>D:<img src='https://img2.meite.com/questions/202303/146410278d24d10.png' /></li></ul><p>答 案:D</p><p>解 析:由题知0<α<兀,而<img src="https://img2.meite.com/questions/202303/1464102b0581dad.png" />,故<img src="https://img2.meite.com/questions/202303/1464102b0b41884.png" />,因此<img src="https://img2.meite.com/questions/202303/1464102b0fe7c88.png" />.</p><p class="introTit">主观题</p><p>1、在△ABC中,已知三边 a、b、c 成等差数列,且最大角∠A是最小角的2倍, a: b :c.
</p><p>答 案:<img src="https://img2.meite.com/questions/202303/296423b0ae0659d.png" /></p><p>2、设函数f(x)<img src="https://img2.meite.com/questions/202303/296423a66bbdb95.png" />且f'(-1)=-36
(Ⅰ)求m
(Ⅱ)求f(x)的单调区间</p><p>答 案:(Ⅰ)由已知得f'=<img src="https://img2.meite.com/questions/202303/296423a74f41b7f.png" /> 又由f'(-1)=-36得
6-6m-36=-36
故m=1.
(Ⅱ)由(Ⅰ)得f'(x)=<img src="https://img2.meite.com/questions/202303/296423a792d1aff.png" />
令f'(x)=0,解得<img src="https://img2.meite.com/questions/202303/296423a7b14cf3f.png" />
当x<-3时,f'(x)>0;
当-3<x<2时,f'(x)<0;
当x>2时,f'(x)>0;
故f(x)的单调递减区间为(-3,2),f(x)的单调递增区间为(-∞,-3),(2,+∞)
</p><p>3、在△ABC中,AB=2,BC=3,B=60°,求AC及△ABC的面积</p><p>答 案:<img src="https://img2.meite.com/questions/202303/296423a37bd555e.png" /></p><p>4、设椭圆的中心是坐标原点,长轴在x轴上,离心率<img src="https://img2.meite.com/questions/202303/2964239c71aeb01.png" />已知点P<img src="https://img2.meite.com/questions/202303/2964239c7e7d039.png" />到圆上的点的最远距离是<img src="https://img2.meite.com/questions/202303/2964239c8cba609.png" />求椭圆的方程
</p><p>答 案:由题意,设椭圆方程为<img src="https://img2.meite.com/questions/202303/2964239cdfdcc2f.png" /> 由<img src="https://img2.meite.com/questions/202303/2964239cef23e00.png" /><img src="https://img2.meite.com/questions/202303/2964239cf5cc660.png" />
设P<img src="https://img2.meite.com/questions/202303/2964239d01ba1aa.png" />点到椭圆上任一点的距离为 d,
<img src="https://img2.meite.com/questions/202303/2964239d0dd8af6.png" />
<img src="https://img2.meite.com/questions/202303/2964239d1e44fb3.png" />则在y=-b时,<img src="https://img2.meite.com/questions/202303/2964239d2c1a969.png" />最大,即d也最大。
<img src="https://img2.meite.com/questions/202303/2964239d43183b3.png" /><img src="https://img2.meite.com/questions/202303/2964239d48e58c6.png" />
<img src="https://img2.meite.com/questions/202303/2964239d5187168.png" />
</p><p class="introTit">填空题</p><p>1、设<img src="https://img2.meite.com/questions/202303/2964239c3b4ac2f.png" />则<img src="https://img2.meite.com/questions/202303/2964239c42d80d7.png" /></p><p>答 案:-1</p><p>解 析:<img src="https://img2.meite.com/questions/202303/2964239ca8a1cc9.png" /> <img src="https://img2.meite.com/questions/202303/2964239cb367f80.png" />
<img src="https://img2.meite.com/questions/202303/2964239cc4f078f.png" />
</p><p>2、<img src="https://img2.meite.com/questions/202303/1464102a1d5eac7.png" />()</p><p>答 案:3</p><p>解 析:<img src="https://img2.meite.com/questions/202303/14641031bbc80a1.png" /></p>