1.(a-b)³-(a-b)²
=(a-b)²(a-b-1)
2.3m(x-y)-n(y-x)
=3m(x-y)+n(x-y)
=(x-y)(3m+n)
3.(x-y)4+x(x+y)³-y(x+y)³
=(x-y) 4+(x+y)³(x-y)
=(x-y)[(x-y)³+(x+y)³]
=(x-y){(x-y+x+y)[(x-y)²-(x-y)(x+y)+(x+y)²]}
=2x(x-y)(x²+3y²)
4.(m-n)(p-q)-(m+n)(p-q)
=(p-q)(m-n-m-n)
=2n(q-p)
5.4p(1-p)³+2(p-1)²
=(1-p)²(4p-4p²+2)
=-2(1-p)²(2P²-2p-1)
1.(x-4)²-(4-x)(8-x)=12
(x-4)(x-4+8-x)=12
4(x-4)=12
x=7
2.(a+b-c)(a-b+c)-(b-a+c)(b-a-c)
=(a-b+c)(a+b-c+b-a+c)
=2b(a-b+c)
因为a-b+c=0
所以原式等于0
3.x(x+y)(x-y)-x(x+y)²
=x(x+y)(x-y-x-y)
=-2xy(x+y)
代入
原式=-12*5=-60