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Matrix multiplication

4 videos
3 skills
You know what a matrix is, how to add them and multiply them by a scalar. Now we'll define multiplying one matrix by another matrix. The process may seem bizarre at first (and maybe even a little longer than that), but there is a certain naturalness to the process. When you study more advanced linear algebra and computer science, it has tons of applications (computer graphics, simulations, etc.)

Multiplying a matrix by a matrix

PRACTICE PROBLEMS
Multiply two matrices

Multiplying a matrix by a vector

PRACTICE PROBLEMS
Multiply a matrix by a vector

Defined and undefined matrix operations

PRACTICE PROBLEMS
Determine whether the addition, subtraction, or multiplication of two matrices is defined