# What's the unit matrix ?

Apr 27, 2018

check the explanation below

#### Explanation:

It's a matrix whose main diagonal elements are all $1$ and zeroes elsewhere denoted by $I$

and it's a square matrix $\left({I}_{n}\right)$

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Example:

${I}_{2} = \left(\begin{matrix}1 & 0 \\ 0 & 1\end{matrix}\right)$

${I}_{3} = \left(\begin{matrix}1 & 0 & 0 \\ 0 & 1 & 0 \\ 0 & 0 & 1\end{matrix}\right)$