4x²+2xy-2y²+4x+7y-3=(2x-y+3)(2x+2y-1)因为 4x²+2xy-2y²=(2x-y)(2x+2y)所以设 4x²+2xy-2y²+4x+7y-3=(2x-y+a)(2x+2y-b)所以 4x²+2xy-2y²+4x+7y-3=4x²+2xy-2y²+2a...