- #1
forty
- 135
- 0
A matrix P is called idempotent if P^2 = P. If P is idempotent and P =/= I show that det(P)=0.
I don't really know where to go with this but i have a feeling that it involves taking the det of each side.
det(P^2) = det(P)
det(P)det(P) = det(P)
where to from here if that's even the right step/method to take, or if its even right at all >_>
Thanks :)
I don't really know where to go with this but i have a feeling that it involves taking the det of each side.
det(P^2) = det(P)
det(P)det(P) = det(P)
where to from here if that's even the right step/method to take, or if its even right at all >_>
Thanks :)