1/4(x-1)^2=1/9(x+1)^2[1/2(x-1)]^2=[1/3(x+1)]^2x>=1时1/2(x-1)=1/3(x+1)1/2x-1/2=1/3x-1/31/6x=1/6x=11>x>-1时1/2(1-x)=1/3(x+1)1/2-1/2x=1/3x+1/31/6=5/6xx=1/5x