(1) 4x^2-4x+2m-m^2 (2)9x^2-6x+2y-y^2 (3)若3n^2-n=1,求6n^3+7n^2-5n+2003的值拜托各位了 3Q
问题描述：
(1) 4x^2-4x+2m-m^2 (2)9x^2-6x+2y-y^2 (3)若3n^2-n=1,求6n^3+7n^2-5n+2003的值拜托各位了 3Q
答
(1)4x^2-4x+2m-m^2=(2x+m)(2x-m)-2(2x-m)=(2x-m)(2x+m-2)(2)9x^2-6x+2y-y^2=(3x-1)^2-(y-1)^2=(3x+y-2)(3x-y)(3)若3n^2-n=1,3n^2-n-1=06n^3+7n^2-5n+2003=6n^3-2n^2-2n+9n^2-3n-3+2006=2n(3n^2-n-1)+3(3n^2-n-1)+2006=2006