2x-1/x+1+3x+1/x+2-5x-11/x-1=

问题描述:

2x-1/x+1+3x+1/x+2-5x-11/x-1=

(2x-1)(x+2)(x-1)+(3x+1)(x+1)(x-1)-(5x-11)(x+1)(x+2)
=2x²-31x-21