Khan Academy: Transformations and Matrix Multiplication: Matrix Product Examples

Providing the motivation for definition of matrix products in this short video.

Explains what the zero matrix is and how it is used in matrix multiplication. [4:41]

The class explores a real-world application in which the data represents rental prices of beach condos. They problem solve by multiplying matrices to determine the cost of each property in each season. Several scenarios are presented in...

Showing that matrix products are associative in this short video.

Just as any number remains the same when multiplied by 1, any matrix remains the same when multiplied by the identity matrix. [7:59]

Find the image of a given polygon under a transformation defined by a given matrix. Students receive immediate feedback and have the opportunity to try questions repeatedly, watch a video or receive hints.

Visualize matrix multiplication on the coordinate plane. Pupils use the interactive to create a matrix multiplication problem using vectors. The scholars see the resulting product of the matrices as a vector.

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 shows example of adding and subtracting rational expressions. Includes discussion of using the least common multiple of the denominators for a common denominator. [2:56]

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:...