A 22-minute video lesson on the inverse of a matrix. 4 examples solved step by step using the method of algebraic cofactors.
I show how to quickly compute the inverse of a matrix by writing the algebraic cofactors directly into the resulting matrix.
Table of Contents:
- What is the inverse of a matrix? (definition) [00:39]
- Identity matrix [01:13]
- Feasibility of calculating the inverse of a matrix (square matrices only) [02:18]
- Calculating the inverse of a 1×1 matrix [02:42]
- Formula for the inverse of a matrix [03:36]
- Calculating the inverse of a 2×2 matrix (using the formula) [04:23]
- Calculating the inverse of a 3×3 matrix (using the formula) [12:11]
- Calculating the inverse of 4×4 and higher-order matrices [21:00]
Homework
Download Answers to Homework (PDF)
Articles and blog posts related to this Lesson
- “The biggest problem with Matrix problems”
- “Solving systems of equations using the inverse matrix method”
- “Inverse matrix calculated using the Gauss-Jordan elimination method”