Most impactful lecture from college—matrix determinants: Low road: define formula, prove zero iff invertible Middle road: define as function that is zero iff invertible, prove it is unique, derive formula High road: construct via exterior product space Seek better abstractions.
Greg Brockman
 @gdb
23 Apr 2022
With proper abstraction, all bugs become shallow.

Apr 23, 2022 · 4:32 PM UTC

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Replying to @gdb
Underground road: ad-bc, memorize or lose the points
Replying to @gdb
GIF
Replying to @gdb
Computer science terminology in college sure changed from when I was in the first comp sci graduating class at UCLA in 1973.
Replying to @gdb
I loved the constructive derivation so much I reproduced it on my (mostly inactive) blog. mtskw.com/posts/determinant/ I went YEARS without seeing this, things became so intuitive once I did (like why zero det means you can’t invert)

A Constructive Derivation of the Determinant

Deriving the determinant formula from intuitive properties of volumes.

mtskw.com
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Replying to @gdb
everything will be elliptical curves... forever...