3a(m-n)-2b(m-n) =(m-n)(3a-2b)a(x-2)-b(x-2)+(2-x) =(x-2)(a-b-1)9(a-b)(a+b)-3(a-b)'2 =3(a-b)(3a+3b-a+b)=6(a-b)(a+2b)-2(b-2a)'2+(b-2a)=(b-2a)(4a-2b+1)3(x+y)(y-x)-(x-y)'2=(y-x)(3x+3y-y+x)=2(y-x)(2x-y)-3(x-y)'2-(y-x)'3=(y-x)²(x-y-3)