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# Basic matrix operations

5 videos
5 skills
Keanu Reeves' virtual world in the The Matrix (I guess we can call all three movies "The Matrices") have more in common with this tutorial than you might suspect. Matrices are ways of organizing numbers. They are used extensively in computer graphics, simulations and information processing in general. The super-intelligent artificial intelligences that created The Matrix for Keanu must have used many matrices in the process. This tutorial introduces you to what a matrix is and how we define some basic operations on them.

### Introduction to the matrix

VIDEO 4:29 minutes

### Matrix dimensions

PRACTICE PROBLEMS
Identify the dimensions of a matrix

### Representing data with matrices

VIDEO 5:43 minutes

### Representing relationships with matrices

PRACTICE PROBLEMS

### Scalar multiplication

VIDEO 2:18 minutes

### Scalar matrix multiplication

PRACTICE PROBLEMS
Multiply a matrix by a scalar

### Matrix addition and subtraction

VIDEO 5:35 minutes

### Matrix addition and subtraction

PRACTICE PROBLEMS
Add and subtract matrices

### Transpose of a matrix

VIDEO 3:42 minutes

### Matrix transpose

PRACTICE PROBLEMS
Transpose a matrix