《高中数学必修二题专讲练》由会员分享，可在线阅读，更多相关《高中数学必修二题专讲练（15页珍藏版）》请在金锄头文库上搜索。
1、Evaluation only.Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd.Copyright 2004-2011 Aspose Pty Ltd.作业解析求圆心在直线3x+y-5=0上，并且经过原点和点（3，-1） 的圆的方程。设圆的圆心坐标为（a，b），已知圆经过原点和点（ 3，-1
2、）， 代入圆的标准方程得又已知（a，b）在直线3x+y-5=0，所以3a+b-5=0 解方程组3a+b-5=0a=5/3b=0Evaluation only.Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd.Copyright 2004-2011 Aspose Pty Ltd.1.判断两直线
3、的位置关系若直线l1:A1x+B1y+C1=0，直线 l2:A2x+B2y+C2=0则l1 l2A1A2+B1B2=0当A1，A2，B1，B2全不为0时，Evaluation only.Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd.Copyright 2004-2011 Aspose P
4、ty Ltd.2.画直观图的方法：斜二侧法xyEvaluation only.Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd.Copyright 2004-2011 Aspose Pty Ltd.3.平面内一点P(x0,y0) 到直线Ax+By+C=0的距离公式是6.Evaluation
5、only.Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd.Copyright 2004-2011 Aspose Pty Ltd.如图，正方体ABCD-A1B1C1D1的棱长为2,它的各个顶点 都在球O的球面上，问球O的表面积。ABCDD1C1B1A1OABCDD1C1B1A1O分析：正方体
6、内接于球，则由球和正方体都是中心对称图形可 知，它们中心重合，则正方体对角线与球的直径相等。 略解：关键：找正方体的棱长a与球半径R之间的关系Evaluation only.Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd.Copyright 2004-2011 Aspose Pty Ltd
7、.ABCDD1C1B1A1O Evaluation only.Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd.Copyright 2004-2011 Aspose Pty Ltd.56565343Evaluation only.Evaluation only. Created with A
8、spose.Slides for .NET 3.5 Client Profile 5.2.0.0.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd.Copyright 2004-2011 Aspose Pty Ltd.直线l过点（-1，-2）和第二、三、四象限，若l 在两坐标轴上的截距之和为-6，求直线l的方程。解：设直线方程为：已知点（-1，-2）在直线上，所以截距之和为-6 ，所以a+b=-6 解方程组：a+b=-6a=-2b=-4或a=-3b
9、=-3 所以直线l的方程为：4x+2y+8=0或x+y+3=0Evaluation only.Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd.Copyright 2004-2011 Aspose Pty Ltd.已知关于x，y的方程C: （1）若方程C表示圆，求a的取值范围。 （2）若a=
10、4，圆C与直线x-2y+4=0相交于A,B两点 ，求A,B两点的距离。解（1）由圆的一般公式满足的条件 ：（2）因为a=4，圆C方程：x-2y+4=0x=0或8/5y=2或14/5即A(0,2),B(8/5,14/5);则Evaluation only.Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pt
11、y Ltd.Copyright 2004-2011 Aspose Pty Ltd.三垂线定理三垂线定理在在平面内平面内的一条直线，如果它和这个平面的的一条直线，如果它和这个平面的一条斜线的射影垂直，那么它也和这条斜线垂直一条斜线的射影垂直，那么它也和这条斜线垂直P PA AO OaEvaluation only.Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.
12、 Copyright 2004-2011 Aspose Pty Ltd.Copyright 2004-2011 Aspose Pty Ltd.P PA AO Oa三垂线定理的逆定理三垂线定理的逆定理在平面内的一条直线，如果它和这个平面在平面内的一条直线，如果它和这个平面的一条斜线垂直，那么它也和这条斜线在平面的一条斜线垂直，那么它也和这条斜线在平面内的射影垂直内的射影垂直Evaluation only.Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Created with Aspo
13、se.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd.Copyright 2004-2011 Aspose Pty Ltd.如图：在棱长为a的正方体A1B1C1D1-ABCD中， （1）证明B1D面A1BC1 （2）若以A为坐标原点，分别以AB、AD、AA1所 在的直线为x轴、y轴、z轴建立空间直角坐标系， 试写出c和c1两点的坐标。C1CAA1DBD1B1PDB1C1BCAA1D1xzyEvaluation only.Evaluation only. Created with Asp
14、ose.Slides for .NET 3.5 Client Profile 5.2.0.0.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd.Copyright 2004-2011 Aspose Pty Ltd.已知ABCD是矩形，P是矩形所在平面外 一点，且PA平面ABCD，M、N分别是 BC，PD中点， 求证：(1) MN /平面PAB(2)MNADBPNMCDAEFEvaluation only.Evaluation only. Creat
15、ed with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd.Copyright 2004-2011 Aspose Pty Ltd.Evaluation only.Evaluation only. Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0.Created with Aspose.Slides for .NET 3.5 Client Profile 5.2.0.0. Copyright 2004-2011 Aspose Pty Ltd.Copyright 2004-2011 Aspose Pty Ltd.
