Compute A+B if A=[1 2; 3 4] and B=[0 1; -1 5].

Exercise · ZW-MATRIX-003 · ★☆☆ Basic

Compute \(A+B\) if \(A=\begin{pmatrix}1&2\\3&4\end{pmatrix}\) and \(B=\begin{pmatrix}0&1\\-1&5\end{pmatrix}\).

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Matrices of the same size are added entry by entry: \((A+B)_{ij}=a_{ij}+b_{ij}\). The result is \(\begin{pmatrix}1&3\\2&9\end{pmatrix}\).

A matrix \(A\) is a rectangular array of numbers arranged in rows and columns; with \(m\) rows and \(n\) columns, it has size \(m\times n\).

\[A=\begin{pmatrix}a_{11}&\cdots&a_{1n}\\ \vdots&\ddots&\vdots\\ a_{m1}&\cdots&a_{mn}\end{pmatrix}\]