已知函数f(x)=-x+log2(1-x)/(1+x),则f(1/2011)+f(-1/2011)的值为?
问题描述：
已知函数f(x)=-x+log2(1-x)/(1+x),则f(1/2011)+f(-1/2011)的值为?
答
f(x)+f(-x)
=-x+log2[(1-x)/(1+x)]+x+log2[(1+x)/(1-x)]
=log2{[(1-x)/(1+x)][(1-x)/(1+x)]}
=log2(1)
=0
所以原式=0