因式分解:;
(1)(x²+2x+2)(x²+2x+4)-3
(2)(x+1)(x-2)(x+3)(x-4)+24
(3)abx²+(a²+b²)xy-(a²-b²)y
因式分解:;
(1)(x²+2x+2)(x²+2x+4)-3
(2)(x+1)(x-2)(x+3)(x-4)+24
(3)abx²+(a²+b²)xy-(a²-b²)y
(x²+2x+2)(x²+2x+4)-3=[(x²+2x+3)-1][(x²+2x+3)+1]-3
=(x²+2x+2)^2-1-3
=(x²+2x+2)^2-4
=(x²+2x+2+2)(x²+2x+2-2)
=x(x+2)(x²+2x+4)
(x+1)(x-2)(x+3)(x-4)+24=(x^2-x-2)(x^2-x-12)+24
=[(x^2-x-7)+5][(x^2-x-7)-5]+24
=(x^2-x-7)^2-25+24
=(x^2-x-7+1)(x^2-x-7-1)
=(x^2-x-6)(x^2-x-8)
=(x-3)(x+2)(x^2-x-8)