计算:(x-4y)(2x+3y)-(x+2y)(x-y).
问题描述:
计算:(x-4y)(2x+3y)-(x+2y)(x-y).
答
原式=2x2+3xy-8xy-12y2-x2+xy-2xy+2y2=x2-4xy-10y2.
计算:(x-4y)(2x+3y)-(x+2y)(x-y).
原式=2x2+3xy-8xy-12y2-x2+xy-2xy+2y2=x2-4xy-10y2.