用十字相乘怎么解呢?4x²-4xy+y²+6x-3y-10(x-1)(x+2)(x-3)(x+4)+24希望能有过程.
问题描述:
用十字相乘怎么解呢?
4x²-4xy+y²+6x-3y-10
(x-1)(x+2)(x-3)(x+4)+24
希望能有过程.
答
4x²-4xy+y²+6x-3y-10
=(2x-y)²+3(2x-y)-10
=(2x-y+5)(2x-y-2)
(x-1)(x+2)(x-3)(x+4)+24
=(x²+x-2)(x²+x-12)+24
=(x²+x)²-14(x²+x)+24+24
=(x²+x-6)(x²+x-8)
=(x-2)(x+3)(x²+x-8)