## Derivative of matrix inverse

The matrix Sigma is positive definite and is decomposed as $\Sigma = AA^T$

Thus: $\Sigma^{-1} = A^{-T}A^{-1}$ and $A^{T}\Sigma^{-1} = A^{-1}$

What is $\frac{d A^{-1}}{d\Sigma}$ ?