Question

How do you find `M^2` given `M=((2,0), (0, 2))`?

Answer 1

`((4, 0), (0, 4))`

Explanation:

`M = 2I` is a simple scalar multiple of the `2xx2` identity matrix.

So `M^2 = (2I)(2I) = 4I^2 = 4I = ((4, 0), (0, 4))`

Scalar multiplication commutes with matrix multiplication.

Answer 2

It is

`M^2=((2,0), (0, 2))*((2,0), (0, 2))=((2*2+0*0,2*0+0*2),(0*2+2*0,0*0+2*2))=((4,0),(0,4))`