Talk:Partial inverse of a matrix

Broken source, small math mistake
Point 1: reference Seems to be broken, it leads to a 404.

Point 2: the given case for $${a_{kk}}$$



\left[ \operatorname{inv}_k (A) \right]_{ij} = \begin{cases} \frac{1}{a_{kk}} & i = j = k \\ -\frac{a_{kj}}{a_{kk}} & i = k, j \neq k \\ \frac{a_{jk}}{a_{kk}} & i \neq k, j = k \\ a_{ij} - \frac{a_{ik} a_{kj}}{a_{kk}} & i \neq k, j \neq k \end{cases} $$

seems to have a typo for case $$ i \neq k, j = k $$, it should be $$ \frac{a_{ik}}{a_{kk}}$$.

Plnts (talk) 18:40, 14 July 2022 (UTC)