Now, |A| = bc =

Hence, A ^{– 1} exists.

Cofactors of A are

C₁₁ =

C₁₂ = – c

C₂₁ = – b

C₂₂ = a

Since, adj A =

(adj A) =

=

Now, A ^{– 1} = .adj A

A ^{– 1} = .

A ^{– 1} =