inverse matrices

Question

if c = 

2	-4	12
0	6	-12
1	-2	3

and d=

(1/6) times

1	2	4
2	1	-4
1	0	-2

are C and D inverse matrices?

Answer 1

and .

 

If and are inverse matrices then .

Find .

Find .

Hence  .

Thus  and  are inverses.