# Pre-Calculus 12: Matrices & Matrix Applications

## Video Lectures

Displaying all 33 video lectures.

Lecture 1Play Video |
What is a Matrix? 1In this video I will define what is a matrix and its rows and columns. Next video in the Matrices series can be seen at: http://youtu.be/YTV7ei1hyJI |

Lecture 2Play Video |
What is a Matrix? 2In this video I will explain the matrix elements and its i, j (row, column) subscripts, mxn matrix. Next video in the Matrices series can be seen at: http://youtu.be/AaMIgwKtShQ |

Lecture 3Play Video |
Row Echelon FormIn this video I will explain and show an example of a row-echelon form matrix. Next video in the Matrices series can be seen at: http://youtu.be/uDNeLykDJas |

Lecture 4Play Video |
Reduced Row Echelon FormIn this video I will show how to reduce a row echelon form matrix. Next video in the Matrices series can be seen at: http://youtu.be/ElFIbVBZe8k |

Lecture 5Play Video |
Method of Gaussian Elimination: ExampleIn this video I will use the method of Gaussian elimination to solve for the unknowns. Next video in the Matrices series can be seen at: http://youtu.be/5mD_CnbC7Zk |

Lecture 6Play Video |
Method of Gaussian Elimination: 2x2 MatrixIn this video I will use the method of Gaussian elimination to solve for a 2x2 matrix. Next video in the Matrices series can be seen at: http://youtu.be/5EeqBabPSzg |

Lecture 7Play Video |
Method of Gaussian Elimination: 3x3 Matrix*In this video I will use the method of Gaussian elimination to solve for a 3x3 matrix. Next video in the Matrices series can be seen at: http://youtu.be/ux2K_v63F0Y |

Lecture 8Play Video |
Gaussian Elimination: 3x3 Matrix, No SolutionIn this video I will use the method of Gaussian elimination to solve for a system of 3 linear equations with no solution. Next video in the Matrices series can be seen at: http://youtu.be/aZgC7FnT9Ok |

Lecture 9Play Video |
Gaussian Elimination: 3x3, Infinite SolutionsIn this video I will use the method of Gaussian elimination to solve for a system of 3 linear equations with infinite number of solutions. Next video in the Matrices series can be seen at: http://youtu.be/0D5z9WbdsBI |

Lecture 10Play Video |
Gaussian Elimination: Example of Solving 3x3In this video I will use the method of Gaussian elimination to find x=? y=? z=? of a 3 equation 3 unknown system of equations. Next video in the Matrices series can be seen at: http://youtu.be/_numHGhNrZI |

Lecture 11Play Video |
What are Equal Matrices?In this video I will explain what are equal matrices. Next video in the Matrices series can be seen at: http://youtu.be/sQ4od79mGRA |

Lecture 12Play Video |
How to Add MatricesIn this video I will find the sum of 2 matrices. Next video in the Matrices series can be seen at: http://youtu.be/BLBG-9p3faw |

Lecture 13Play Video |
How to Subtract MatricesIn this video I will find the difference of 2 matrices. Next video in the Matrices series can be seen at: http://youtu.be/DrR7z20PWEg |

Lecture 14Play Video |
How to Multiply Matrices by a NumberIn this video I will find the scalar products with matrices. Find C=? if 4B=C where B and C are 2x2 matrices. Next video in the Matrices series can be seen at: http://youtu.be/6NVZBJGszjU |

Lecture 15Play Video |
How to Solve Mixed Operations on MatricesIn this video I will find A-2B=? where A and B are matrices, mixed operations with matrices. Next video in the Matrices series can be seen at: http://youtu.be/NTk1GcYqzUc |

Lecture 16Play Video |
How to Multiply (Square) MatricesIn this video I will explain the condition needed for square matrices multiplication. Next video in the Matrices series can be seen at: http://youtu.be/Sxyde1xtkpU |

Lecture 17Play Video |
How to Multiply (Different Size) MatricesIn this video I will explain the condition needed for 2 matrices (of different sizes) multiplication. Next video in the Matrices series can be seen at: http://youtu.be/fQp_X2JGbp0 |

Lecture 18Play Video |
Matrices that CANNOT be Multiplied TogetherIn this video I will explain why 2 matrices (3x1 and 2x3) cannot be multiplied together. Next video in the Matrices series can be seen at: http://youtu.be/iAZa-ysy_uQ |

Lecture 19Play Video |
What is an Identity Matrix?In this video I will define, explain, and find the identity matrices to 1x1, 2x2, and 3x3 matrices. Next video in the Matrices series can be seen at: http://youtu.be/KoKWMSABkuM |

Lecture 20Play Video |
What is the Inverse of a Matrix?In this video I will define and find the inverse of a 2x2 matrix. Next video in the Matrices series can be seen at: http://youtu.be/F_fyoVXaowY |

Lecture 21Play Video |
Using the Determinant to Find the InverseIn this video I will find the inverse of a 2x2 matrix using a determinant, method 1. Next video in the Matrices series can be seen at: http://youtu.be/fPHPUDOEn-Q |

Lecture 22Play Video |
Using Gaussian Elimin. to Find the InverseIn this video I will find the inverse of a 2x2 matrix using a the Gaussian elimination method. Next video in the Matrices series can be seen at: http://youtu.be/SfZa9Y0ZTfQ |

Lecture 23Play Video |
Finding the Inverse of a 3x3 MatrixIn this video I will find the inverse of a 3x3 matrix using a the Gaussian elimination method. Next video in the Matrices series can be seen at: http://youtu.be/WKmPLI-y1wc |

Lecture 24Play Video |
Dividing One Matrix by Another MatrixIn this video I will find the division of one matrix by another matrix. Next video in the Matrices series can be seen at: http://youtu.be/X8AG-gkifeU |

Lecture 25Play Video |
Solving Sys of Linear Eqn with InverseIn this video I will explain how to find x=? y=? of systems of 2 linear equations using inverse matrices. Next video in the Matrices series can be seen at: http://youtu.be/kQjTb6qtim0 |

Lecture 26Play Video |
Solving Sys of Linear Eqn with InverseIn this video I will find x=? y=? of systems of 2 linear equations using inverse matrices. Next video in the Matrices series can be seen at: http://youtu.be/yJ-vSmO-Ogg |

Lecture 27Play Video |
Solving Sys of Linear Eqn with InverseIn this video I will find x=? y=? of 2 systems of 2 linear equations using determinants. Next video in the Matrices series can be seen at: http://youtu.be/wKUOJ8DjeLw |

Lecture 28Play Video |
Solving Sys of Linear Eqn with InverseIn this video I will find x=? y=? of systems of 3 linear equations using inverse matrices. Next video in the Matrices series can be seen at: http://youtu.be/ZmQoZAh19-c |

Lecture 29Play Video |
Find the Determinant of a 2x2 MatrixIn this video I will find the determinant of a 2x2 matrix. Next video in the Matrices series can be seen at: http://youtu.be/6MWu4BPR4Qs |

Lecture 30Play Video |
Find the Determinant of a 3x3 Matrix 1In this video I will find the determinant of a 3x3 matrix by breaking a 3x3 matrix into 3-2x2 matrices. Next video in the Matrices series can be seen at: http://youtu.be/WsoPIeJj4X4 |

Lecture 31Play Video |
Find the Determinant of a 3x3 Matrix 2In this video I will find the determinant of a 3x3 matrix by using the “diagonal” method. Next video in the Matrices series can be seen at: http://youtu.be/JMjuaMY5BsQ |

Lecture 32Play Video |
Using Cramer's Rule to Find x=? y=?In this video I will find x=? y=? of systems of 2 linear equations using Cramer's rule. Next video in the Matrices series can be seen at: http://youtu.be/UfwXTMygeVs |

Lecture 33Play Video |
Using Cramer's Rule to Find x=? y=? z=?In this video I will find x=? y=? z=? of systems of 3 linear equations using Cramer's rule. First video in the Matrices series can be seen at: https://youtu.be/pSgaeGFyLH0 |