Let and a = 4, b = –2.

Show that:

A(BC) = (AB)C

To prove: A(BC) = (AB)C

LHS = A(BC) =

⇒ LHS =

⇒ LHS =

⇒ LHS =

RHS = (AB)C =

Performing matrix multiplication as done for LHS

⇒ RHS =

⇒ RHS =

Clearly LHS = RHS =

∴ A(BC) = (AB)C …proved