Скачать или смотреть Example 2 Matrix matrix multiplication via linear combinations of columns

We do our second example of right matrix-matrix multiplication (MMM) to swap the second and third columns of a matrix leaving all other columns untouched.

00:00 -Introduction
00:18 -Problem statement: swap columns 2 and 3 of a matrix
00:33 -The first of four versions of matrix-matrix multiplication
00:44 -To do work on the columns, multiply modeling matrix on the right
01:24 -Use a transposition matrix to swap columns
02:14 -You are genius: pause video and do this example for yourself
02:38 -If you need it, Jeff guide to creating a 2nd brain for this example
02:55 -Calculate column 1: right MMM via linear combinations of columns
04:13 -Calculate column 2: right MMM via linear combinations of columns
05:25 -Good habits to reduce mental friction in writing mathematics
05:50 -How can I make my work clear to understand this in 10 years?
06:20 -Calculate column 3: right MMM via linear combinations of columns
07:13 -Point of example: train your brain & do active recall deliberate practice
07:42 -Calculate column 4: right MMM via linear combinations of columns
08:28 -Combine all results together to form product
09:47 -Challenge 1: How to do general permutation of columns of a matrix?
10:17 -Conclusion