Khan Academy: Finding Inverses of Matrices: Example of Finding Matrix Inverse

Defining the determinant for nxn matrices. An exampled of a 4x4 determinant.

Figuring out the formula for a 2x2 matrix. Defining the determinant.

Finding the determinant by going along other rows or columns

Learn how to verify whether two functions are inverses by their composition. Students are given examples and practice problems.

Video first explains and gives examples of identity matrices. Then explains what an inverse matrix is and shows how to calculate the inverse of a 2x2 matrix. [14:14]

Video example of finding the inverse of a 3 by 3 matrix. Includes using expansion by minors to determine the determinant and finding the matrix of cofactors and adjugate or adjoint matrix. This video also appears in the strand Algebra:...

Video shows how to determine the inverse of a 3 by 3 matrix using the Gauss-Jordan elimination method. This video also appears in the strand Algebra: Matrices. [13:35]

Video explains why a matrix is singular if its determinant is 0. Illustrates that when a matrix equation is built with a singular matrix, then there are no solutions because the system it represents is that of two parallel lines. Shows...

The final segment in the Khan Academy's series on function inverses. Similar to the previous video, this segment does another example for finding the inverse of a quadratic function. Again the instructor explains the need for restraints...

This lesson goes through three examples of matrix multiplication. Explains how the dimensions of matrices affect whether or not the matrices can be multiplied, how to determine if they can be multiplied, and what size the resulting...