And, just a little bit of notation, So, they would call this matrix.

And that notation is Sigma notation.

It's just all notation there's nothing particular about notation.

Sigma notation up.

The determinant of X, the determinant of matrix X and hopefully you're maybe a bit comfortable with writing sigma notation, we did this in the last matrix.

This is another notation.

I always forget notation.

Yeah, see that notation?

And the general notation if I remember it correctly is that anything that's a matrix or a vector is bolded.

And I'll introduce my notation.

This is just my notation.

I'm just making up notation.

These are all equivalent notation.

I'll use the same notation.

This is just different notation.

We've seen this notation before.

And the notation is PV

Very, very specific encrypted notation.

We've learned about matrix addition, matrix subtraction, matrix multiplication.

Matrix

Matrix

Matrix

Matrix

So, this is just all notation of what a matrix is it's a table of numbers, it can be represented this way.

The identity matrix times any other matrix is just that matrix.

And it's a very subtle notation.

Write your answer using exponential notation.

This is just a Leibniz notation.

That's what this sigma notation is.

This is, I believe, Leibniz's notation.

I have all the sigma notation.

This is just notation right here

So an identity matrix is a matrix.

The Matrix

Blast Matrix