1.(m+n)(n-m)-n(m+n)(m-n) 2.3a(x-y)-(x-y)a 3.(x-y)²-2(y-x) 4.(m+n)(p+q)-(m+n)(q+p)

问题描述:

1.(m+n)(n-m)-n(m+n)(m-n) 2.3a(x-y)-(x-y)a 3.(x-y)²-2(y-x) 4.(m+n)(p+q)-(m+n)(q+p)
5.m(x-y)²-x+y
5(y-x)²+3(x-y) 15*(a-b)²-3y(b-a) 6(m-n)³-12(n-m)²

1.(m+n)(n-m)-n(m+n)(m-n)
=(m+n)(n-m)-n(m+n)[-(n-m)]
=(m+n)(n-m)+n(m+n)(n-m)
=(m+n)(n-m)(1+n)
2.3a(x-y)-(x-y)a
=(x-y)(3a-a)
=2a(x-y)
3.(x-y)²-2(y-x)
=(x-y)²-2[-(x-y)]
=(x-y)²+2(x-y)
=(x-y)(x-y+2)
4.(m+n)(p+q)-(m+n)(q+p)
=(m+n)(p+q)-(m+n)(p+q)
=0
5.m(x-y)²-x+y
=m(x-y)²-(x-y)
=(x-y)[m(x-y)-1]
=(x-y)(mx-my-1)