分解因式x(b+c-d)-y(d-c-b)-2c+2d-2b
问题描述：
分解因式x(b+c-d)-y(d-c-b)-2c+2d-2b
答
=xb+xc-xd-yd+yc+yb-2c+2d-2b
=b(x+y-2)+c(x+y-2)-d(x+y-2)
=(b+c-d)(x+y-2)