Show that the square matrix $\displaystyle 2N - I$ is its own inverse if $\displaystyle N^{2} = N$
I really don't know where to start here. All I know is that I have to show that $\displaystyle 2N - I = (2N - I)^{-1}$.
Any help is appreciated.
Show that the square matrix $\displaystyle 2N - I$ is its own inverse if $\displaystyle N^{2} = N$
I really don't know where to start here. All I know is that I have to show that $\displaystyle 2N - I = (2N - I)^{-1}$.
Any help is appreciated.