What is a unit matrix?

1 Answer
Dec 17, 2014

The unit matrix is every nx n square matrix made up of all zeros except for the elements of the main diagonal that are all ones.
For example:
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It is indicated as In where n representes the size of the unit matrix.

The unity matrix in linear algebra works a little bit like the number 1 in normal algebra so that if you multiply a matrix by the unit matrix you get the same initial matrix!