初中数学,因式分解!1.-28m^2-3m^3+m^42.a^n+1-5a^n+6a^n-13.(2a^2-3)^2-(11a-3)^24.1+1/64c^25.-x^2-4y^2+4xy6.a^2+ab-ac-bc7.x^3+x^2y-xy^2-y^38.4b^2c^2-(b^2+c^2-a^2)^29.x^4+410.(y^2-5y)^2+10(y^2-5y)+2411.x^3-7x+612.x^6+26x^3-27

Question

初中数学,因式分解!
1. -28m^2-3m^3+m^4
2. a^n+1-5a^n+6a^n-1
3. (2a^2-3)^2-(11a-3)^2
4. 1+1/64c^2
5. -x^2-4y^2+4xy
6. a^2+ab-ac-bc
7. x^3+x^2y-xy^2-y^3
8. 4b^2c^2-(b^2+c^2-a^2)^2
9. x^4+4
10.(y^2-5y)^2+10(y^2-5y)+24
11. x^3-7x+6
12. x^6+26x^3-27

Answer 1

1. -28m^2-3m^3+m^4
=m^2(m-7)(m+4)
2. a^n+1-5a^n+6a^n-1
=a^(n-1)(a-3)(a-2) 注：（n-1)是次方
3. (2a^2-3)^2-(11a-3)^2
=a(2a-11)(2a-1)(a+6)
4. 1+1/64c^2
=
5. -x^2-4y^2+4xy
=-(x-2Y)^2
6. a^2+ab-ac-bc
=(a+b)(a-c)

7. x^3+x^2y-xy^2-y^3
=(x+y)^2(x-y)
8. 4b^2c^2-(b^2+c^2-a^2)^2
=(a+b-c)(a-b+c)(a+b+c)(b+c-a)

9. x^4+4
=
10.(y^2-5y)^2+10(y^2-5y)+24
=(y-1)(y-2)(y-3)(y-4)
11. x^3-7x+6
=

12. x^6+26x^3-27
=(x-1)(x^2+x+1)(x^3+27)