题目

化简x^2-4x+4/2x-4 3x^2-9x-12/x^2+2x+1 x^2-7x+12/-x^2+9x-20 xy-x-y+1/y^2-2y+1
(1)x^2-4x+4/2x-4
(2) 3x^2-9x-12/x^2+2x+1
(3)x^2-7x+12/-x^2+9x-20
(4)xy-x-y+1/y^2-2y+1

提问时间：2020-08-07

答案

(1)x^2-4x+4/2x-4=(x-2)^2/2(x-2)=x-2/2(2)3x^2-9x-12/x^2+2x+1=3(x^2-3x-4)/(x+1)^2=3(x+1)(x-4)/(x+1)^2=3(x-4)/x+1(3)原式=(x-6)(x-1)/-(x-1)(x+10）=x-6/-(x+10)(4)原式=x(y-1)-(y-1)/(y-1)^2=(x-1)(y-1)/(y-1)^...