Uploaded August 2026 | Updated September 2026, 1 week ago
Master the method of minors and cofactors to find the determinant of a 3x3 matrix! This video provides a comprehensive, step-by-step guide with examples and strategic tips to simplify your calculations.
In this tutorial, you will learn:
Understanding Determinants: What the vertical bars mean and why we calculate determinants.
Choosing a Row or Column: How to strategically select a row or column (especially those with zeros) to minimize work.
Calculating Minors: How to find the determinant of the 2x2 matrix formed by crossing out rows and columns.
Applying Cofactors: Using the (-1)^(row + column) rule to determine the sign of each term.
Step-by-Step Calculation: Detailed walkthroughs of combining minors and cofactors to find the 3x3 determinant.
Simplifying with Zeros: See how choosing a row or column with zeros drastically reduces calculation steps.
We'll go through four examples together, including practice problems, to ensure you fully grasp this essential linear algebra concept. Perfect for students in algebra, pre-calculus, or linear algebra courses!
Timestamps:
00:00 - Introduction to Method of Minors and Cofactors
0:20 - Example 1: Calculating Determinant using the First Row
0:50 - Setting up Minors and Cofactors for Each Element
1:50 - Calculating 2x2 Determinants and Simplifying
3:05 - Final Determinant for Example 1
3:25 - Strategic Tip: Choosing Rows/Columns with Zeros
4:00 - Example 2: Utilizing Zeros for Simpler Calculation
4:20 - Setting Up Minors and Cofactors for the Second Row
5:20 - Simplifying with Zeros to Find the Determinant
6:10 - Practice Example 3: Pause and Try on Your Own!
6:50 - Solution for Practice Example 3 (Using Zeros)
8:00 - Practice Example 4: Pause and Try on Your Own!
8:20 - Mario's Math Tutoring Channel Membership Information
9:40 - Solution for Practice Example 4
Don't forget to like, comment, and subscribe for more math tutorials!
#Determinant #Matrix #MinorsAndCofactors #LinearAlgebra #MathTutorial #3x3Matrix #AlgebraHelp #PreCalculus
Learn More Here:
Shortcut for finding the Determinant of a 3x3 Matrix
youtu.be/mHsm9oe8n1U
Matrices Playlist
youtube.com/playlist?list=PLHRatQsym1_h8QT2pXuCs-Q2GdJGKjPnU
➡️JOIN the channel as a CHANNEL MEMBER at the "ADDITIONAL VIDEOS" level to get access to my math video courses(Algebra 1, Algebra 2/College Algebra, Geometry, PreCalculus), midterm & final exam reviews, ACT and SAT prep videos and more! (Over 390+ videos)
youtube.com/channel/UClOR1BiPyOkkIAnv9Cmj4iw/join
Master the method of minors and cofactors to find the determinant of a 3x3 matrix! This video provides a comprehensive, step-by-step guide with examples and strategic tips to simplify your calculations.
In this tutorial, you will learn:
Understanding Determinants: What the vertical bars mean and why we calculate determinants.
Choosing a Row or Column: How to strategically select a row or column (especially those with zeros) to minimize work.
Calculating Minors: How to find the determinant of the 2x2 matrix formed by crossing out rows and columns.
Applying Cofactors: Using the (-1)^(row + column) rule to determine the sign of each term.
Step-by-Step Calculation: Detailed walkthroughs of combining minors and cofactors to find the 3x3 determinant.
Simplifying with Zeros: See how choosing a row or column with zeros drastically reduces calculation steps.
We'll go through four examples together, including practice problems, to ensure you fully grasp this essential linear algebra concept. Perfect for students in algebra, pre-calculus, or linear algebra courses!
Timestamps:
00:00 - Introduction to Method of Minors and Cofactors
0:20 - Example 1: Calculating Determinant using the First Row
0:50 - Setting up Minors and Cofactors for Each Element
1:50 - Calculating 2x2 Determinants and Simplifying
3:05 - Final Determinant for Example 1
3:25 - Strategic Tip: Choosing Rows/Columns with Zeros
4:00 - Example 2: Utilizing Zeros for Simpler Calculation
4:20 - Setting Up Minors and Cofactors for the Second Row
5:20 - Simplifying with Zeros to Find the Determinant
6:10 - Practice Example 3: Pause and Try on Your Own!
6:50 - Solution for Practice Example 3 (Using Zeros)
8:00 - Practice Example 4: Pause and Try on Your Own!
8:20 - Mario's Math Tutoring Channel Membership Information
9:40 - Solution for Practice Example 4
Don't forget to like, comment, and subscribe for more math tutorials!
#Determinant #Matrix #MinorsAndCofactors #LinearAlgebra #MathTutorial #3x3Matrix #AlgebraHelp #PreCalculus
Learn More Here:
Shortcut for finding the Determinant of a 3x3 Matrix
youtu.be/mHsm9oe8n1U
Matrices Playlist
youtube.com/playlist?list=PLHRatQsym1_h8QT2pXuCs-Q2GdJGKjPnU
➡️JOIN the channel as a CHANNEL MEMBER at the "ADDITIONAL VIDEOS" level to get access to my math video courses(Algebra 1, Algebra 2/College Algebra, Geometry, PreCalculus), midterm & final exam reviews, ACT and SAT prep videos and more! (Over 390+ videos)
youtube.com/channel/UClOR1BiPyOkkIAnv9Cmj4iw/join
