1- 2/(x+1)= (x-1)/(x+1),
所以 h(x)=ln[(x-1)/(x+1)] = ln(x-1)- ln(x+1),
而 h(-x)=ln[(-x-1)/(-x+1)]=ln[(x+1)/(x-1)]=ln(x+1)-ln(x-1),
所以 h(x)= -h(-x) ,是奇函数.