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Inverse via the adjoint

A−1=1∣A∣adj⁡A(∣A∣≠0)A^{-1} = \frac{1}{|A|}\operatorname{adj}A \qquad (|A| \neq 0)
AA
a square matrix
∣A∣|A|
the determinant of A
adj⁡A\operatorname{adj}A
the adjugate — transpose of the cofactor matrix

The inverse of a non-singular matrix is its adjugate divided by its determinant.

43
questions use it
31
of them past-year
2017–2026
years it has appeared
30%
rated HARD
4
exams
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