Matrices: left inverse is also right inverse?
3301
If $AB = I$ then $BA = I$
122434
Adjoint of a matrix and inverse of a matrix
149292
Inverse of a diagonal matrix plus a constant
101452
How is the determinant related to the inverse of matrix?
66995
Why is a projection matrix symmetric?
134075
Inverse of $A^{-1}+B^{-1}$
5644
Is a right inverse of a surjective linear map linear?
148946
If $\mathbf{A}$ is a $2\times 2$ matrix that satisfies $\mathbf{A}^2 - 4\mathbf{A} - 7\mathbf{I} = \mathbf{0}$, then $\mathbf{A}$ is invertible
33559
Product or sum of invertible matrix give an invertible matrix?
137920
Proving an equation with invertible matrices
107900
A ring which has many distinct left inverses
17997
Right identity and Right inverse implies a group
6324
Deriving the inverse of a 2x2 matrix
86919
When (and more importantly, why) does $AA^T$ have an inverse?
25159
Why does the inverse of the Hilbert matrix have integer entries?
85550
Positive definiteness of difference of inverse matrices
130268
How to prove that a nilpotent matrix is not invertible?