Let A, B be two 3 × 3 matrices with entries from real numbers. Which one of the following is true?
(A+B)3=A3+3A2B+3AB2+B3
(AB)2=O⇒AB=O
(A+B)(A−B)=A2−B2
(A+B)A=BA+A2
(a), (b), (c) cannot hold in general unless AB=BA