Prove that if the matrices A and B commute (AB=BA) than the equations:
[tex]a) (A+B)^2=A^2+2AB+B^2 ; b) (A+B)^2=A^3+3A^2B+3AB^2+B^3[/tex]
The Attempt at a Solution
How will I start solving this task? Should I chose two commute matrices ? How will I know what matrices to choose?