解答初一因式分解18道 急需 快！！最好要过程。谢谢20分！！

有些难题:如下，运用整体思想，不是所有的都会做，哈哈
17）=m(m-3)(m-2)(m-1)-3=(m^2-3m)(m^2-3m+2)-3=(m^2-3m)+2(m^2-3m)-3=
(m^2-3m+3)(m^2-3m-1)

1. x^2-y^2-1+2y
2. x^2-1-y^2+xy^2
3. x^3+12x-6x^2-8
4. x^3+2x-3
5. x^2-xy-2y^2+x+7y-6
6. x^3-4x^2+5x-2
7. x^2-y^2-x+1/4
8. x^2+y^2+4x^2y^2+1/4
9. xy-3x+6y-18
10. ax^2+ax+a+b+bx+bx^2
11. a^2-b^2+2a-c^2+1-2bc
12. x^3-x^2-2x+y^3+y^2-2y
13. a^2-2ab+b^2-2a+2b-3
14. x^3-2x-1
15. a^3+a^2-2
16. x^3-x-6
17. m(m-1)(m-2)(m-3)-3
18. x^2+xy-6y^2+x+13y-6

1. x^2-y^2-1+2y =x^2-(y^2+1-2y)=x^2-(y-1)^2=(x-y+1)(x+y-1)

1. x^2-y^2-1+2y =x^2-(y^2+1-2y)=x^2-(y-1)^2=(x-y+1)(x+y-1)

分太少了
题太多了

(1) x^2-y^2-1+2y =x^2-(y^2+1-2y)=x^2-(y-1)^2=(x-y+1)(x+y-1)
(2) x^2-1-y^2+xy^2=(x+1)(x-1)+y^2(x-1)=(x-1)(x+1+y^2)
(3)这题初中不要求学.