满分5 >
初中数学试题 >
(2002•湘西州)在Rt△ABC中,∠C是直角,各边的长度都分别扩大2倍,那么...
(2002•湘西州)在Rt△ABC中,∠C是直角,各边的长度都分别扩大2倍,那么∠A的三角函数值( )
A.没有变化
B.分别扩大2倍
C.分别扩大
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131021232602463334902/SYS201310212326024633349012_ST/0.png)
倍
D.不能确定
考点分析:
相关试题推荐
(2002•大连)在Rt△ABC中,∠C=90°,c=5,a=4,则sinA的值( )
A.
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131021232602463334902/SYS201310212326024633349011_ST/0.png)
B.
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131021232602463334902/SYS201310212326024633349011_ST/1.png)
C.
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131021232602463334902/SYS201310212326024633349011_ST/2.png)
D.
查看答案
(2002•广西)在Rt△ABC中,∠ACB=90°,CD⊥AB垂足为D,且CD=3,AC=5,则cosB等于( )
A.
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131021232602463334902/SYS201310212326024633349010_ST/0.png)
B.
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131021232602463334902/SYS201310212326024633349010_ST/1.png)
C.
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131021232602463334902/SYS201310212326024633349010_ST/2.png)
D.
查看答案
(2002•苏州)如图,△ABC中,∠C=90°,BC=2,AB=3,则下列结论中正确的是( )
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131021232602463334902/SYS201310212326024633349009_ST/images0.png)
A.sinA=
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131021232602463334902/SYS201310212326024633349009_ST/0.png)
B.cosA=
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131021232602463334902/SYS201310212326024633349009_ST/1.png)
C.sinA=
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131021232602463334902/SYS201310212326024633349009_ST/2.png)
D.tanA=
查看答案
(2002•潍坊)如图,点A、B、C、D、E、F分别是小正方形的顶点,在△ABC与△DEF中,下列结论成立的是( )
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131021232602463334902/SYS201310212326024633349008_ST/images0.png)
A.∠BAC=∠EDF
B.∠DFE=∠ACB
C.∠ACB=∠EDF
D.这两个三角形中没有相等的角
查看答案
(2003•成都)在△ABC中,已知AC=3,BC=4,AB=5,那么下列结论成立的是( )
A.sinA=
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131021232602463334902/SYS201310212326024633349007_ST/0.png)
B.cosA=
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131021232602463334902/SYS201310212326024633349007_ST/1.png)
C.tanA=
![manfen5.com 满分网](http://img.manfen5.com/res/CZSX/web/STSource/20131021232602463334902/SYS201310212326024633349007_ST/2.png)
D.cotA=
查看答案