满分5 >
高中数学试题 >
从4名男生和3名女生中选出4人参加某个座谈会,若这4人中必须既有男生又有女生,则...
从4名男生和3名女生中选出4人参加某个座谈会,若这4人中必须既有男生又有女生,则不同的选法共有( )
A.140种
B.120种
C.35种
D.34种
考点分析:
相关试题推荐
指数函数y=f(x)的反函数的图象过点(2,-1),则此指数函数为( )
A.
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131024182646104347862/SYS201310241826461043478008_ST/0.png)
B.y=2
xC.y=3
xD.y=10
x
查看答案
若
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131024182646104347862/SYS201310241826461043478007_ST/0.png)
,且x∈(-π,π),则x的值( )
A.
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131024182646104347862/SYS201310241826461043478007_ST/1.png)
B.
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131024182646104347862/SYS201310241826461043478007_ST/2.png)
或
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131024182646104347862/SYS201310241826461043478007_ST/3.png)
C.
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131024182646104347862/SYS201310241826461043478007_ST/4.png)
D.
查看答案
已知函数f(x)在[-5,5]上是偶函数,f(x)在[0,5]上是单调函数,且f(-3)<f(-1),则下列不等式一定成立的是( )
A.f(-1)<f(3)
B.f(2)<f(3)
C.f(-3)<f(5)
D.f(0)>f(1)
查看答案
双曲线
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131024182646104347862/SYS201310241826461043478005_ST/0.png)
的焦点是F
1,F
2,点P是双曲线上一点,若
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131024182646104347862/SYS201310241826461043478005_ST/1.png)
=0,则△PF
1F
2的面积是( )
A.9
B.12
C.15
D.20
查看答案
a、b是直线,α、β是平面,下列判断正确的是( )
A.a垂直于α内无数条直线,则a⊥α
B.a⊥b,b⊥α,则a∥α
C.a∥α,b⊥α,则a⊥b
D.若a∥α,α∥β,则a∥β
查看答案