Question 476558
<pre>
Here is the 4×4 unit matrix:

{{{(matrix(4,4,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1))}}}

Here is the 4×4 identity matrix:

{{{(matrix(4,4,1,0,0,0,0,1,0,0,0,0,1,0,0,0,0,1))}}}

A unit matrix is a square matrix all of whose elements are 1's.

An identity matrix is a square matrix whose upper left to lower
right diagonal elements are 1's and all the other elements
are 0's.

Edwin</pre>