f( x)=tanx+log2[(1+x)/(1-x)]+1
f(1/2)=tan(1/2)+log2[(3/2)/(1/2)]+1
=tan(1/2)+log2(3)+1
f(-1/2)=tan(-1/2)+log2[(1/2)/(3/2)]+1
=-tan(1/2)+log2(1/3)+1
=-tan(1/2)-log2(3)+1
∴f(1/2)+f(-1/2)=2
f( x)=tanx+log2[(1+x)/(1-x)]+1
f(1/2)=tan(1/2)+log2[(3/2)/(1/2)]+1
=tan(1/2)+log2(3)+1
f(-1/2)=tan(-1/2)+log2[(1/2)/(3/2)]+1
=-tan(1/2)+log2(1/3)+1
=-tan(1/2)-log2(3)+1
∴f(1/2)+f(-1/2)=2