1.(x+2)(y+3)-(x+1)(y-2)2.6x~2=(3x-2)(1-2x)+(x+2)(3-x)其中小x=-1

热心网友

1. xy+3x+2y+6-xy+2x-y+2=5x+y+82.6x^2=3x-6x^2-2+4x^2+3x-x^2+6-2x9x^2=4x+4x=2/9加减2/9根号10