1
1) x^3-x = x(x^2-1)
2) y^4+y = y(y^3+1)
3) b^4-b^5 = b^4(1-b)
4) 7c^4-9c^2 = c^2(7c^2-9)
5) 18m^14-27m^7=9m^7(2m^7-3)
6) -72n^5-27n^10=-9n^5(8+3n^5)
2
1) x(a-x)+y(x-a)=x(a-x)-y(a-x)=(a-x)(x-y)
4) (a-b)^2-a(b-a)^2=(a-b)^2-a(a-b)^2=(a-b)^2*(1-a)
2) b(c-b)-d(b-c)=b(c-b)+d(c-b)=(c-b)(b+d)
5) (x-y)^2+b(y-x)=(x-y)(x-y)-b(x-y)=(x-y)(x-y-b)
3) 2x(3x-5)+17(5-3x)=2x(3x-5)-17(3x-5)=(3x-5)(2x-17)
6) a(x-5)^2-b(5-x)=a(x-5)^2+b(x-5)=a(x-5)(x-5)+b(x-5)=(x-5)(ax-5a+b)
3
1) a(b-c)+10(b-c)=(b-c)(a+10)
5) (a-b)^2+3(a-b)=(a-b)(a-b)+3(a-b)=(a-b)(a-b+3)
2) 7(a+x)-b(a+x)=(a+x)(7-b)
6) (x-1)^2+7(x-1)=(x-1)(x-1)+7(x-1)=(x-1)(x-1+7)=(x-1)(x+6)
3) c(a+b)+(a+b)=(a+b)(c+1)
7) (b+5)^2-b(b+5)=(b++5)-b)=(b+5)(b+5-b)=5(b+5)
8) -2a(a+4)+(a+4)^2=(a++(a+4))=(a+4)(4-a)
