(x+y)(x-y)-(x-y)²-6x²y除猜世皮2y+(2xy)²除(-4xy)
=x²-y²穗差-x²+2xy-y²-6x²-xy
=-6x²-2y²+xy
当x=-2,y=1/3
原式=-24-2/9-2/返猛3
=-24又8/9
化简求值(x+y)(x-y)-(x-y)²-6x²y除2y+(2xy)²除(-4xy)其中x=-2,y=1/3
(x+y)(x-y)-(x-y)²-6x²y除猜世皮2y+(2xy)²除(-4xy)
=x²-y²穗差-x²+2xy-y²-6x²-xy
=-6x²-2y²+xy
当x=-2,y=1/3
原式=-24-2/9-2/返猛3
=-24又8/9