Question

prove that x^3+=(x+y)(x^2+y^2-xy)

Answer 1

$= x.x2−x2y+x.y2+y.x2−x.y2+y.y2</p><p>= x3−x2y+xy2+x2y−xy2+y3</p><p>= x3+y3</p><p>So, L.H.S = R.H.S</p><p>x3+y3=x3+y3</p><p>Hence, x3+y3=(x+y)(x2−xy+y2) is derived.</p><p></p><p>$