Question

What is the identity matrix for subtraction?

Answer 1

Assuming we're talking about 2x2 matrices, the identity matrix for subtraction is the same as that for addition, namely:

`(0, 0)`
`(0, 0)`

The identity matrix for multiplication and division is:

`(1, 0)`
`(0, 1)`

There are analogous matrices of larger size, consisting of all `0`'s or all `0`'s except for a diagonal of `1`'s.