设偶函数f(x)满足f(x)=2的x次-4(x>且=0)则{x|f(x-2)>0}=?A{x|x4} Bx4 Cx6 Dx2
问题描述：
设偶函数f(x)满足f(x)=2的x次-4(x>且=0)则{x|f(x-2)>0}=?A{x|x4} Bx4 Cx6 Dx2
答
x-2>=0
则f(x-2)=2^(x-2)-4>0
2^(x-2)>4=2^2
x-2>2
x>4
x-2=0
偶函数f(x-2)=f(2-x)=2^(2-x)-4>0
2-x>2
x