Question

find matrix B such that AB=I. verify If A= 1 0 0, 5 1 0, 1 3 1 that BA = I.
​

Answer 1

Answer:

Let A=⎛⎝⎜111124135⎞⎠⎟ and D=⎛⎝⎜200030005⎞⎠⎟.

It is found that right-multiplication by D multiplies each column of A by the corresponding diagonal entry of D, whereas left-multiplication by D multiplies each row of A by the corresponding diagonal entry of D.

Construct a 3 x 3 matrix B, not the identity matrix or zero matrix, such that AB=BA.

,