化简:x/(x+1)-(x+3)/(x+1)×(x^2-1)/(x+2)^2-1,再选一个你认为运算方便的数代入求值
问题描述：
化简:x/(x+1)-(x+3)/(x+1)×(x^2-1)/(x+2)^2-1,再选一个你认为运算方便的数代入求值
答
2X X+3 X -1--- - --- * --------2X+1 X+1 (X+2)-1x x+3 (x+1)(x-1)= --- - --- * ---------------x+1 x+1 (x+2-1)(x+2+1) ===》（x+1)(x+3)x x+3 x-1= --- - --- * ---x+1 x+1 x+3x (x-3)(x-1）= --- - ----------x...