How to Multiply Matrices
Multiplying matrices is painless when you understand the method described here.
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You Will Need
- Compatible matrices
- Calculator
Steps
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Step 1
Check rows and columns
Makes sure the number of columns in the first matrix equals the number of rows in the second.
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Unless the number of columns in the first matrix equals the number of rows in the second, their product will be undefined.
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Step 2
Calculate the (row 1, column 1) entry
Place the sum of the products from row 1 of the first matrix and column 1 of the second matrix in the (row 1, column 1) position of the product matrix.
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Step 3
Calculate the (row 2, column 1) entry
Place the sum of the products from row 2 of the first matrix and column 1 of the second matrix in the (row 2, column 1) position of the product matrix.
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Step 4
Calculate the remaining entries
Continue multiplying the elements of the rows of the first matrix by the elements of the columns in the second matrix until you have formed a product matrix with the dimensions of (rows of the first matrix) by (columns of the second matrix).
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The word matrix comes from the Latin word for mother.
