# 15.2: Matrix Addition

- Page ID
- 106897

The sum of two matrices \(\mathbf{A}\) and \(\mathbf{B}\) (of the same dimensions) is a new matrix of the same dimensions, \(\mathbf{C}\) = \(\mathbf{A}\)+ \(\mathbf{B}\). The sum is defined by adding entries with the same indices: \(c_{ij}=a_{ij}+b_{ij}\).

\[\begin{pmatrix} 3 &-2 &4 \\ 5 &3i &3 \\ -i & 1/2 &9 \end{pmatrix}+\begin{pmatrix} 0 &2 &1 \\ -4 &-2i &i\\ -i & 1/2 &-5 \end{pmatrix}=\begin{pmatrix} 3 &0 &5 \\ 1 &i &3+i\\ -2i & 1 &4 \end{pmatrix} \nonumber\]

Need help? The link below contains solved examples: Matrix addition: http://tinyurl.com/m5skvpy

External links:

- Matrices: Basic Matrix Operations (add, subtract, multiply by constant) http://patrickjmt.com/matrices-basic-matrix-operations-add-subtract-multiply-by-constant/