Expanding:
- (a + b)2 = (a + b)(a + b) = (a2 + 2ab + b2)
- (a – b)2 = (a – b)(a – b) = (a2 – 2ab + b2)
- (a – b)2 = (a – b)(a – b) = (a2 + 2ab + b2)
- (a2 – b2) = (a + b)(a b)
- (a + b)3 = (a + b)(a + b)(a + b) = (a3 + 3a2b + 3ab2 + b3)
- a(a -1) = a2 – a
- 3(b + 1) = 3b + 3
Factoring:
- (a2 + 2ab + b2) = (a + b)(a + b) = (a + b)2
- (a2 – 2ab + b2) = (a – b)(a – b) = (a – b)2
- (a2 + 2ab + b2) = (a – b)(a – b) = (a – b)2
- (a + b)(a b) = (a2 – b2)
- (a3 + 3a2b + 3ab2 + b3) = (a + b)(a + b)(a + b) = (a + b)3
- a2 – a = a(a -1)
- 3b + 3 = 3(b + 1)