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Matrix Multiplication

Last updated: 1/9/2025

Questions

Notes

Matrix multiplication is used EVERYWHERE, there are 3 ways to multiply out a matrix.

  1. Entry by entry. To multiply matrix A by B, take every row in A and multiply it by every column in B, if A is mxn and B is nxp, then the resuling matrix should be mxp
  2. Rows and columns. If you are multiplying matrix A by matrix B, then you can multiply the matrix A by the columns of B or multiply the matrix B by the columns of A.
  3. Parts of matricies (split up the matrix into equal parts and multiply them out like you do in entry by entry).

See Also