(2x-y)(3x-2y)+(y-x)(2x+5y)
问题描述:
(2x-y)(3x-2y)+(y-x)(2x+5y)
答
(2x-y)(3x-2y)+(y-x)(2x+5y)
=6x²-3xy-4xy+2y²+5y²-2x²+5xy-2xy
=6x²-2x²-7xy+3xy+2y²+5y²
=4x²-4xy+7y²