因式分解;1.x^2-xy-2y^2-x+5y-22 .(b-c)^2-4(a-b)(c-a) 3.(x^2-3x-3)(x^2-_数学解答

因式分解;1.x^2-xy-2y^2-x+5y-2
2 .(b-c)^2-4(a-b)(c-a) 3.(x^2-3x-3)(x^2-3x-5)-35 4.(x+1)(x-2)(x-3)(x-6)+20 5.(x+1)(x+2)(x+7)(x+8)+8 6.a^4+4

人气：169 ℃　时间：2020-03-22 12:23:51

解答

1.x^2-xy-2y^2-x+5y-2 =(x^2-xy-2y^2)+(-x+5y)-2 =(x-2y)(x+y)+(-x+5y)-2 =(x-2y+1)(x+y-2)