(1)(v-2u)^2-(2u-v)(u+2v)-2v+4u=(v-2u)^2+(v-2u)(2v+u)-2(v-2u)=(v-2u)(v-2u+2v+u-2)
=(v-2u)(3v-u-2)
(2)2x(-1+2y)-6y(2+y)=2[-x+4y-6y-3y^2]=2(-x-2y-3y^2)2x(-1+2y)-6x(2+y)写错了sorry，能再做一次吗？2x(-1+2y)-6x(2+y)=2x(-1+2y-6-3y)=2x(-y-7)=-2x(y+7)