2025年高职单招《数学(中职)》每日一练试题03月13日

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03/13
<p class="introTit">单选题</p><p>1、不等式<img src="https://img2.meite.com/questions/202409/1066dff8ed59cbe.png" />的解集为()</p><ul><li>A:<img src='https://img2.meite.com/questions/202409/1066dff8f34133c.png' /></li><li>B:<img src='https://img2.meite.com/questions/202409/1066dff8f8d9ab2.png' /></li><li>C:<img src='https://img2.meite.com/questions/202409/1066dff8ff1317f.png' /></li><li>D:<img src='https://img2.meite.com/questions/202409/1066dff9056a321.png' /></li></ul><p>答 案:B</p><p>解 析:<img src="https://img2.meite.com/questions/202409/1066dff90babc9a.png" /></p><p>2、若椭圆<img src="https://img2.meite.com/questions/202409/1866ea8b09dfd7d.png" />的离心率为<img src="https://img2.meite.com/questions/202409/1866ea8b12f06e1.png" />,则 m的值为()  </p><ul><li>A:<img src='https://img2.meite.com/questions/202409/1866ea8b19ab946.png' /></li><li>B:<img src='https://img2.meite.com/questions/202409/1866ea8b207e543.png' /></li><li>C:<img src='https://img2.meite.com/questions/202409/1866ea8b264286e.png' /></li><li>D:<img src='https://img2.meite.com/questions/202409/1866ea8b2bbc955.png' /></li></ul><p>答 案:C</p><p>解 析:当m+9>9,即m>0时,<img src="https://img2.meite.com/questions/202409/1866ea9387d0b1c.png" />,则<img src="https://img2.meite.com/questions/202409/1866ea9396bba55.png" />,解得m=3;当m+9<9,即m<0时,<img src="https://img2.meite.com/questions/202409/1866ea93a955af6.png" />,则<img src="https://img2.meite.com/questions/202409/1866ea93b0e0c0c.png" />,解得<img src="https://img2.meite.com/questions/202409/1866ea93b69e0cb.png" /></p><p>3、已知椭圆<img src="https://img2.meite.com/questions/202409/2066ed2c3fc91a2.png" />的两个焦点为F<sub>1</sub>,F<sub>2</sub>,过F<sub>2</sub>的直线交椭圆于M,N两点,则△F<sub>1</sub>MN的周长为()  </p><ul><li>A:2</li><li>B:4</li><li>C:6</li><li>D:8</li></ul><p>答 案:D</p><p>解 析:易知椭圆<img src="https://img2.meite.com/questions/202409/2066ed2c3fc91a2.png" />的长半轴长a=2.又M,N是椭圆上的点,F<sub>1</sub>,F<sub>2</sub>是椭圆的焦点,所以<img src="https://img2.meite.com/questions/202409/2066ed2c5d25e08.png" /><img src="https://img2.meite.com/questions/202409/2066ed2c66081c3.png" />,所以△F<sub>1</sub>MN的周长为<img src="https://img2.meite.com/questions/202409/2066ed2c7521872.png" />=2a+2a=4a=8。</p><p class="introTit">主观题</p><p>1、已知<img src="https://img2.meite.com/questions/202501/1167822ff243cf5.png" /></p><p>答 案:方法一:矢量图表示法 矢量图表示法如图所示。<img src="https://img2.meite.com/questions/202501/1167822ff89fe55.png" /><img src="https://img2.meite.com/questions/202501/1167822ffb0aba3.png" /> 方法二:矢量表示法<img src="https://img2.meite.com/questions/202501/116782300184954.png" /></p><p>解 析:<img src="https://img2.meite.com/questions/202409/1366e3aff07aaa2.png" /><img src="https://img2.meite.com/questions/202409/1366e3affb6a19c.png" /><img src="https://img2.meite.com/questions/202409/1366e3affff2ae2.png" /></p><p class="introTit">填空题</p><p>1、在△ABC中,若B=30°,BC=4,AB=5,则△ABC的面积为()</p><p>答 案:5</p><p>解 析:<img src="https://img2.meite.com/questions/202409/1466e544485da6a.png" /></p><p>2、函数y=-x<sup>2</sup>+4x+1的单调递增区间是()  </p><p>答 案:(-∞,2]</p><p>解 析:因为函数y=-x<sup>2</sup>+4x+1的图像开口向下,对称轴为直线x=2,所以该函数的单调递增区间为(-0,2]</p><p>3、如图,在正方体ABCD-A<sub>1</sub>B<sub>1</sub>C<sub>1</sub>D<sub>1</sub>中,M,N分别为棱C<sub>1</sub>D<sub>1</sub>,C<sub>1</sub>C的中点,则以下四个结论正确的是().(填写正确结论的编号)① 直线 AM 与CC<sub>1</sub>是相交直线;②直线 AM 与 BN 是平行直线;③ 直线 BN 与MB<sub>1</sub>是异面直线;④ 直线 AM 与DD<sub>1</sub>是异面直线. <img src="https://img2.meite.com/questions/202409/1366e3e3688c863.png" />  </p><p>答 案:③④</p><p>解 析:易知A,M,C<sub>1</sub>均在平面AD<sub>1</sub>C<sub>1</sub>B中,但<img src="https://img2.meite.com/questions/202409/1366e3f805b0cee.png" />所以直线AM与 CC<sub>1</sub>是异面直线.同理,AM 与 BN是异面直线,BN与 MB<sub>1</sub>是异面直线,AM 与 DD<sub>1</sub>是异面直线,故 ①② 错误,③④ 正确.</p><p class="introTit">简答题</p><p>1、在(2x-3y)<sup>9</sup>的展开式中,求:(1)二项式系数之和;<br />(2)各项系数之和.  </p><p>答 案:(1)易知(2x-3y)<sup>9</sup>的展开式的二项式系数之和为2<sup>9</sup>= 512 (2)令x=y=1,得(2-3)<sup>9</sup>=-1, 所以(2x-3y)<sup>9</sup>的展开式的各项系数之和为-1.  </p>
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