急求几道因式分解题的详细解题过程及答案~!

问题描述:

急求几道因式分解题的详细解题过程及答案~!
1)1-25b²
2)(a+b)²-1
3)m²(m-n)+(n-m)
4)x²-x-6
5)4a²-b²+4a+1
6)3x²+8x-3

3a-b)²-4(3a-b)(a+3b)+4(a+3b)² 其实这就是一个完全平方式
=[3a-b-2(a+3b)]²
=(3a-b-2a-6b)²
=(a-7b)²
分解因式2a^4-3a^2-14=?(在实数范围内)
2a^4-3a^2-14
=(2a²-7)(a²+2)
=(a√2-√7)(a√2+√7)(a²+2)
(x^2-1)(x^4+x^2+1)-(x^3+1)^2
=(x^2)^3-1-(x^3+1)^2
=x^6-1-(x^6+2x^3+1)
=-2x^3-2
=-2(x^3+1)
=-2(x+1)(x^2-x+1)
x(x+y)(x-y)-x(y+x)²
=x(x+y)(x-y-y-x)
=-2xy(x+y)
x^2-(m^2+n^2)x+mn(m^2-n^2)
=(x-m^2+mn)(x-n^2-mn)