Question

把下列各式分解因式.1）a^3+b^3-ab(a+b) 2)x^2-y^2+x+3y-2

Answer 1

1)=a^3+b^3+3(a^2)b+3a(b^2)-4ab(a+b)

=(a+b)^3-4ab(a+b)

=(a+b)((a+b)^2-4ab)

=(a+b)(a-b)^2

2)=x^2+x+1/4-(y^2-3y+9/4)

=(x+1/2)^2-(y-3/2)^2

=(x+y-1)(x-y+2)