# How the idea of adjugate matrix has been designed? [closed]

I can understand the adjugate matrix and the motivation of that to find the inverse, but I can't see how this idea was invented by mathematicians. It's just brilliance or someone understand how the properties were conceived.

I trying to understand this property origins, but I can't explain how cofactor were created too:

$$\sum_{i = 1}^n a_{ij} C_{ik}= \begin{cases} \det(A) & \text{if } j = k \\ 0 & \text{if } j \neq k \end{cases}$$

## closed as off-topic by Qiaochu Yuan, Yoav Kallus, Neil Strickland, Ryan Budney, Christian RemlingOct 10 '15 at 3:48

This question appears to be off-topic. The users who voted to close gave this specific reason:

• "This question does not appear to be about research level mathematics within the scope defined in the help center." – Qiaochu Yuan, Neil Strickland, Ryan Budney, Christian Remling
If this question can be reworded to fit the rules in the help center, please edit the question.