- (a + b)2 = a2 + 2ab + b2
- (a – b)2 = a2 – 2ab + b2
- a2 – b2 = (a + b) (a – b)
- (x + a) (x + b) = x2 + (a + b) x +ab
- (a + b)3 = a3 + b3 + 3ab( a + b ) = a3 + b3 + 3a2b + 3ab2
- (a3 + b3) = (a + b)(a2 – ab + b2)
- (a – b)3 = a3 – b3 – 3ab( a – b ) = a3 – b3 – 3a2b + 3ab2
- (a3 – b3) = (a – b)(a2+ ab + b2)
- (a3 + b3 + b3 – 3abc) = (a + b + c)(a2 + b2 + c2 – ab – bc – ca)
- If (a + b + c) = 0 than (a3 + b3 + b3) = 3abc
- a4 – b4 = (a + b) (a – b)(a2 + b2)