6道分解因式的题目,快,
问题描述：
6道分解因式的题目,快,
1）6ax+3ay-2bx-by
2) x^2y^2-x^2-y^2+1
3) (x^2-x)^2-18(x^2-x)+72
4)(x+1)(x+2)-x-10
5) a^2-2ab+b^2-3a+3b-10
6) x^2-3xy-18y^2-3x-9y
答
1）6ax+3ay-2bx-by
=3a(2x+y)-b(2x+y)
=(3a-b)(2x+y)
2) x^2y^2-x^2-y^2+1
=x^2(y^2-1)-(y^2-1)
=(x^2-1)(y^2-1)
=(x+1)(x-1)(y+1)(y-1)
3) (x^2-x)^2-18(x^2-x)+72
=(x^2-x-6)(x^2-x-12)
=(x-3)(x+2)(x-4)(x+3)
4)(x+1)(x+2)-x-10
=x^2+3x+2-x-10
=x^2+2x-8
=(x+4)(x-2)
5) a^2-2ab+b^2-3a+3b-10
=(a-b)^2-3(a-b)-10
=(a-b-5)(a-b+2)
6) x^2-3xy-18y^2-3x-9y
=(x-6y)(x+3y)-3(x+3y)
=(x+3y)(x-6y-3)