2024年成考高起点《数学(理)》每日一练试题04月11日

聚题库
04/11
<p class="introTit">单选题</p><p>1、过点(-2,2)与直线x+3y-5=0平行的直线是()</p><ul><li>A:x+3y-4=0</li><li>B:3x+y+4=0</li><li>C:x+3y+8=0</li><li>D:3x-y+8=0</li></ul><p>答 案:A</p><p>解 析:所求直线与x+3y-5=0平行,可设所求直线为x+3y+c=0,将点(一2,2)带入直线方程,故-2+3×2+c=0,解得c=-4,因此所求直线为线为x+3y-4=0.</p><p>2、已知集合M =(2,3,5,a),N =(1,3,4,b),若M∩N=(1,2,3),则a,b的值为  </p><ul><li>A:a=2,b=1</li><li>B:a=1,b=1</li><li>C:a=1,b= 2</li><li>D:a=1,b=5</li></ul><p>答 案:C</p><p>解 析:M∩N={2,3,5,a} ∩{1,3,4,6} ={1,2,3} 又因为M中无“1”元素,而有“a”元素,只有a=1 而N中无“2”元素,而有“b元素”,只有b=2  </p><p>3、5名高中毕业生报考3所院校,每人只能报一所院校,则有()种不同的报名方法  </p><ul><li>A:<img src='https://img2.meite.com/questions/202303/28642253cbeb828.png' /></li><li>B:<img src='https://img2.meite.com/questions/202303/28642253cf87ee2.png' /></li><li>C:<img src='https://img2.meite.com/questions/202303/28642253d82d2a0.png' /></li><li>D:<img src='https://img2.meite.com/questions/202303/28642253d319585.png' /></li></ul><p>答 案:C</p><p>解 析:将院校看成元素,高中生看成位置,由重复排列的元素、位置的条件口诀: “元素可挑剩,位置不可缺”,重复排列的种数共有<img src="https://img2.meite.com/questions/202303/286422548fe3345.png" />种,即将元素的个数作为底数,位置的个数作为指数.即:元素(院校)的个数为 3,位置(高中生)的个数为5,共有<img src="https://img2.meite.com/questions/202303/28642254ad8b5e0.png" />种。  </p><p>4、已知α∩β=a,b⊥β,b在α内的射影是b’,那么b'和α的关系是()</p><ul><li>A:b'//α</li><li>B:b'⊥α</li><li>C:b'与α是异面直线</li><li>D:b'与α相交成锐角</li></ul><p>答 案:B</p><p>解 析:<img src="https://img2.meite.com/questions/202303/28642296837771f.png" /> ∴由三垂线定理的逆定理知,b在α内的射影b'⊥α,故选B  </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/202303/28642255fa50503.png" /> (Ⅰ)写出向量<img src="https://img2.meite.com/questions/202303/286422561b1d145.png" />关于基底{a,b,c}的分解式 (Ⅱ)求证:<img src="https://img2.meite.com/questions/202303/286422563d58cde.png" /> (Ⅲ)求证:<img src="https://img2.meite.com/questions/202303/28642256478aacd.png" />  </p><p>答 案:(Ⅰ)由题意知(如图所示) <img src="https://img2.meite.com/questions/202303/286422566983935.png" /> <img src="https://img2.meite.com/questions/202303/28642256740213a.png" /><img src="https://img2.meite.com/questions/202303/286422567c06c5d.png" /> (Ⅱ)<img src="https://img2.meite.com/questions/202303/2864225695c5fbd.png" /><img src="https://img2.meite.com/questions/202303/286422569cdc533.png" /> (Ⅲ)<img src="https://img2.meite.com/questions/202303/28642256a537b6d.png" /> 由已知,a,c是正四棱柱的棱,a,b,c两两垂直 <img src="https://img2.meite.com/questions/202303/28642256d1c4379.png" />  </p><p>2、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>3、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>4、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 class="introTit">填空题</p><p>1、函数<img src="https://img2.meite.com/questions/202303/2864225857f0d64.png" />的图像与坐标轴的交点共有()  </p><p>答 案:2</p><p>解 析:当x=0时,y=<img src="https://img2.meite.com/questions/202303/286422587f2a68b.png" />-2=-1,故函数与y轴交于(0,-1)点,令y=0,则有<img src="https://img2.meite.com/questions/202303/28642258b372965.png" />故函数与x轴交于(1,0) 点,因此函数 <img src="https://img2.meite.com/questions/202303/28642258c6c51c8.png" />与坐标轴的交点共有 2个.</p><p>2、<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>
相关题库