Here we need to see the inverse of a matrix. Provided a square matrix, A, of size n x n if we can get the other matrix of similar size, B that,
AB = BA = In after that we call B the inverse of A and denote it by B=A-1.
Calculating the inverse of a matrix, A, is quite simple. Firstly we form a new matrix,
(A In)
And after that use the row operations from the earlier section and try to change this matrix in the form,
(In B)
If we can so B is the inverse of A. If we can't so there is no inverse of the matrix A.