x分之x+1乘（x+1分之2x）的平方-（x-1分之1-x+1分之1）
=(x+1)/x*[2x/(x+1)]²-[1/(x-1)-1/(x+1)]
=(x+1)/x*4x²/(x+1)²-(x+1-x+1)/(x²-1) 使其有相同项
=4x/(x+1)-2(x²-1) 化简
=4x(x-1)/(x²-1)-2/(x²-1)使分母相同
=(4x²-4x-2)/(x²-1)
好的话,望你采纳,谢谢合作