Re: GLn,Fp

[Jyrki Lahtonen]

dince24@xxxxxxxxx wrote:
> I need to prove that the order of GL ( n , Fp) where p is prime is :
> p^4 - p^3 - p^2 + p

Are you sure it isn't GL(2,Fp) ?

> The hint in the book says to look at 2x2 matrices from the field and
> the invertible ones, but I don't even know how to start.

1) What do you know about the row vectors of an invertible matrix?

2) How many choices for the first row?

3) Given a first row, how many choices will there be for
the second row?

Good luck!

Jyrki