因式分解 1.（v-2u)^2-(2u-v)(u+2v)-2v+4u 2.2x(-1+2y)-6y(2+y)

显示全部楼层 · 2011-10-9 18:44:18

解答：(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)...

千问 · 2011-10-9 18:44:18

（v-2u)^2-(2u-v)(u+2v)-2v+4u=（v-2u)^2+(v-2u)(u+2v)-2(v-2u)=（v-2u)[(v-2u)+(u+2v)-2]=（v-2u)(v-2u+u+2v-2)=（v-2u)(3v-u-2) 2x(-1+2y)-6y(2+y)=2[x(-1+2y)-3y(2+y)]=2(-x+2xy-6y-3y^2)...

千问 · 2011-10-9 18:44:18

1.（v-2u)^2-(2u-v)(u+2v)-2v+4u= （2u-v)^2-(2u-v)(u+2v)+2(2u-v)=(2u-v)(2u-v-u-2v+2)=(2u-v)(u-3v+2)2.2x(-1+2y)-6y(2+y)中间是乘号还是x...