初一的因式分解

1.
(m+n)^2-6(m+n)+9
=(M+N-3)^2

2.
4-12(x-y)+9(x-y)^2
=[3(X-Y)-2]^2

3.
(m^2+n^2）^2-4m^2n^2
=M^4+2M^2N^2+N^4-4M^2N^2
=M^4-2M^2N^2+N^4
=(M^2-N^2)^2

4.
(x^2+y^2-1）^2-4x^2y^2
=(X^2+Y^2)^2-2(X^2+Y^2)+1-4X^2Y^2
=X^4+2X^2Y^2+Y^4-2(X^2+Y^2)+1-4X^2Y^2
=X^4-2X^2Y^2+Y^4-2(X^2+Y^2)+1
=(X^2-Y^2)^2-2(X^2-Y^2)+1-4Y^2
=(x^2-y^2-1）^2-4Y^2
=[(x^2-y^2-1）+2Y]*[(x^2-y^2-1）-2Y]

5.
2(x-y)^3-16(y-x)^2-32(y-x)
=2(X-Y)^3-16(X-Y)^2+32(X-Y)
=2(X-Y)*[(X-Y)^2-8(X-Y)+16]
=2(X-Y)*[(X-Y)-4]^2

1.[(m+n)-3]的平方
2.[3(x-y)-2]的平方
3.(m的平方-n的平方）的平方
4.(x+y+1)(x+y-1)(x-y+1)(x-y-1)
5.2(x-y)乘以(x-y-4)的平方

1.(m+n+3)^2
2.[2-3(x-y)]^2
3.(m^2-n^2)^2
4.(x^2-y^2-1)^2
5. 2(x-y)[(x-y+4)^2]

1.=（m+n-3）^2 ……把m+n看成是x

2.=[2-3(x-y)]^2 ……吧3(x-y)看成是x

3.=(m^2+n^2+2mn)(m^2+n^2-2mn)
=(m+n)^2(m-n)^2

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