Key Terms
Dimensions are written m x n
M rows, n columns.
Given scalar c and matrix A
Every entry a_ij becomes c * a_ij.
Real-world connection
If you need to increase every value in a data matrix by 15%, multiply the whole matrix by 0.15, then add the result back
Example
A is 2x3, B is 3x2. AB will be 2x2.
Steps
1. Store each matrix as a variable: [A], [B], [C] 2.
Matrix
Rectangular array of numbers, named by a capital letter. Entry (element): a single number inside a matrix; identified as
Dimensions
M x n, rows by columns. Square matrix: n x n, equal rows and columns.