Describe how to multiply matrices.

Question
Matrices
asked 2021-02-13
Describe how to multiply matrices.

Answers (1)

2021-02-14
Step 1
Let's take an example to understand clearly
Let \(A=\begin{pmatrix}1 & 2\\3 & 4 \end{pmatrix} , B=\begin{pmatrix}4 & 6\\7 & 8 \end{pmatrix}\)
Step 2
\(A=\begin{pmatrix}1 & 2\\3 & 4 \end{pmatrix} , B=\begin{pmatrix}4 & 6\\7 & 8 \end{pmatrix}\)
\(AB=\begin{pmatrix}1 & 2\\3 & 4 \end{pmatrix}\begin{pmatrix}4 & 6\\7 & 8 \end{pmatrix}\)
Multiply the row of the first matrix by the columns of the second matrix
\(= \begin{pmatrix}1 \cdot 4 + 2 \cdot 7 &1 \cdot 6 + 2 \cdot 8 \\ 3 \cdot 4 + 4 \cdot 7 & 3 \cdot 6 + 4 \cdot 8 \end{pmatrix}\)
\(=\begin{pmatrix}18 & 22\\40 & 50 \end{pmatrix}\)
0

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