m=a+[1/(a-2)],(a>2),n=(1/2)^(x*x-2),(x
问题描述：
m=a+[1/(a-2)],(a>2),n=(1/2)^(x*x-2),(x
答
a>2,a-2>0
M=a+{1/(a-2)}=(a-2)+1/(a-2)+2≥2+2=4
N=(1/2)^(x^2-2)≤(1/2)^(-2)=4
M≥N