(x^2+3x-4)(x^2-x-6)+24
=(x+4)(x-1)(x-3)(x+2)+24
=[(x+4)(x-3)][(x-1)(x+2)]+24
=(x²+x-12)(x²+x-2)+24
=(x²+x)²-14(x²+x)+48(把x²+x看成一个整体再用十字相乘)
=(x²+x-6)(x²+x-8)
=(x+3)(x-2)(x²+x-8)
(x^2+3x-4)(x^2-x-6)+24
=(x+4)(x-1)(x-3)(x+2)+24
=[(x+4)(x-3)][(x-1)(x+2)]+24
=(x²+x-12)(x²+x-2)+24
=(x²+x)²-14(x²+x)+48(把x²+x看成一个整体再用十字相乘)
=(x²+x-6)(x²+x-8)
=(x+3)(x-2)(x²+x-8)