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BobbyTables2today at 2:39 AM1 replyview on HN

Wow, I never realized the cofactor method wasn’t the only one.

I loathed it and it put me off wanting to get into advanced matrix topics.


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RossBencinatoday at 4:42 AM

I don't think determinants play a central role in modern advanced matrix topics.

Luckily for me I read Axler's "Linear Algebra Done Right" (which uses determinant-free proofs) during my first linear algebra course, and didn't concern myself with determinants for a very long time.

Edit: Beyond cofactor expansion everyone should know of at least one quick method to write down determinants of 3x3 matrices. There is a nice survey in this paper:

Dardan Hajriza, "New Method to Compute the Determinant of a 3x3 Matrix," International Journal of Algebra, Vol. 3, 2009, no. 5, 211 - 219. https://www.m-hikari.com/ija/ija-password-2009/ija-password5...

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