1.b(x-y)+c(y-x)=(x-丫)(_____)
2.a(a+b)^2+(b+a)^3中的公因式是_______
3.整式(a+b-c)(a-b+c)+(俾-啊+踩)(b-a-c)的公因式是________
二.
1.-2x^3+6x^2
2.5xy-x^2y+xy^2
3.-6x^3y^4-8x^2y^5+16xy^6
4.2a(a-b)+4a(2a+3b)
5.a(a+b)(a-b)-a(a+b)^2
6.x(x-y)^3+y(y-x)^3
三.求值
1.已知:=78.3,x=-3,y=-7,z=-10,求5ax+5ay-5az的值.
2.已知x+y=3,x*y=2,求-x^2一+y^2一^2-xy^2的值