Let A be a 3x3 matrix which satifies the equation:
A^3 -3A^2 - 10A = 0
a) Find all the real numbers which could possibly be eigenvalues of A
alright... so what i did was simplify the equation and got (A)(A-5)(A+2)=0
but I don't know where to go from there
and
b) Assume, in addition that detA = 20. Find det(A^2 -3A)
I know what to do if i had the matrix but i dont so im kinda lost on this one
thanks