Linear Algebra 47 | Rule of Sarrus [dark version]

[@BariScienceLab]

You’re really good at making these videos!

[@brightsideofmaths]

Thank you so much! :) And thank you for your support!

[@pan19682]

Fascinating presentation many thanks

[@brightsideofmaths]

Glad you enjoyed it

[@wmansour]

Quick reminder for everybody else watching ( i got confused for a while on how to determine if a permutation is positive or negative): 123 (Positive): This is the natural order, so no swaps are needed. Zero is an even number, so this permutation is positive. 132 (Negative): This can be obtained from 123 by swapping 2 and 3, which is one swap (odd), so it's negative. 213 (Negative): This can be obtained from 123 by swapping 1 and 2, which is one swap (odd), so it's negative. 231 (Positive): This can be obtained by two swaps: first swap 1 and 2 to get 213, then swap 1 and 3 to get 231. Two is even, so it's positive. 312 (Positive): Similar to 231, this can be obtained by two swaps from the natural order: first swap 1 and 3 to get 321, then swap 2 and 3 to get 312. Two is even, so it's positive. 321 (Negative): This can be obtained from 123 by swapping 1 and 3, then swapping 2 and 3. However, it can also be obtained by a single swap of the first and last elements of 123. Since one is odd, it's negative.

[@brightsideofmaths]

Nice! :)

[@mnada72]

Please note that in the play list 48 - 52 are out of order