圆心在原点上与直线x+y-2=0相切的圆的方程为 .
考点分析:
相关试题推荐
已知函数f(x)满足:
①定义域为R;
②∀x∈R,有f(x+2)=2f(x);
③当x∈[-1,1]时,f(x)=-|x|+1.
则方程f(x)=log
4|x|在区间[-10,10]内的解个数是( )
A.20
B.12
C.11
D.10
查看答案
图是函数y=Asin(ωx+φ)(x∈R)在区间
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131101225134671622231/SYS201311012251346716222008_ST/0.png)
上的图象,为了得到这个函数的图象,只要将y=sinx(x∈R)的图象上所有的点( )
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131101225134671622231/SYS201311012251346716222008_ST/images1.png)
A.向左平移
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131101225134671622231/SYS201311012251346716222008_ST/1.png)
个单位长度,再把所得各点的横坐标缩短到原来的
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131101225134671622231/SYS201311012251346716222008_ST/2.png)
倍,纵坐标不变
B.向左平移
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131101225134671622231/SYS201311012251346716222008_ST/3.png)
个单位长度,再把所得各点的横坐标伸长到原来的2倍,纵坐标不变
C.向左平移
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131101225134671622231/SYS201311012251346716222008_ST/4.png)
个单位长度,再把所得各点的横坐标缩短到原来的
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131101225134671622231/SYS201311012251346716222008_ST/5.png)
倍,纵坐标不变
D.向左平移
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131101225134671622231/SYS201311012251346716222008_ST/6.png)
个单位长度,再把所得各点的横坐标伸长到原来的2倍,纵坐标不变
查看答案
已知PA垂直于△ABC所在的平面,AB=AC=5,BC=6,PA=8,则P到BC的距离为( )
A.
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131101225134671622231/SYS201311012251346716222007_ST/0.png)
B.
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131101225134671622231/SYS201311012251346716222007_ST/1.png)
C.
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131101225134671622231/SYS201311012251346716222007_ST/2.png)
D.4
查看答案
椭圆
![manfen5.com 满分网](http://img.manfen5.com/res/GZSX/web/STSource/20131101225134671622231/SYS201311012251346716222006_ST/0.png)
上有一点P,它到左准线的距离为5,则P到右焦点的距离为( )
A.7
B.6
C.5
D.4
查看答案
已知m,n为两条不同的直线,α,β为两个不同的平面,则下列命题中正确的是( )
A.α∥β,m⊂α,m⊂β⇒m∥n
B.m⊥α,m⊥n⇒n∥α
C.m⊂α,n⊂α,m∥β,n∥β⇒α∥β
D.m∥n,m⊥α⇒n⊥α
查看答案