来自邓聚龙的问题
计算题多项式乘以多项式3(-4x+y)(x-y)+2(3x-2y)(x+3y)x=-2y=1=(-12x+3y)(x-y)+(6x-4y)(x+3y)=-12x²-12xy+3xy-3y²+6x²+18xy-4xy-12y²=-6x²+5xy-15y²-6×(-2)²+5×(-2)×1-15×(1)²=-6×4+5×(-2)×1-15×1=-2
计算题多项式乘以多项式
3(-4x+y)(x-y)+2(3x-2y)(x+3y)x=-2y=1
=(-12x+3y)(x-y)+(6x-4y)(x+3y)
=-12x²-12xy+3xy-3y²+6x²+18xy-4xy-12y²
=-6x²+5xy-15y²
-6×(-2)²+5×(-2)×1-15×(1)²
=-6×4+5×(-2)×1-15×1
=-24+(-10)-15
=-49
1回答
2020-04-26 08:56