Question 862615
I)
{{{A=(matrix(2,2,6,9,-4,-6))}}}
{{{B=(matrix(2,2,1,2,-1,0))}}}
{{{A^2=(matrix(2,2,0,0,0,0))}}}
{{{A*B=(matrix(2,2,-3,12,2,-8))}}}
{{{B*A=(matrix(2,2,-2,-3,-6,-9))}}}

II)
{{{A=(matrix(2,3,3,-1,4,2,0,6))}}}
{{{B=(matrix(2,3,1,0,-1,0,3,2))}}}
{{{5A=(matrix(2,3,15,-5,20,10,0,30))}}}
{{{3A=(matrix(2,3,9,-3,12,6,0,18))}}}
{{{2B=(matrix(2,3,2,0,-2,0,6,4))}}}
{{{3A-2B=(matrix(2,3,7,-3,14,6,-6,14))}}}