Question I
Let N be the fixed matrix [[0,1],[0,0]].
Consider the linear map T:M2(R)->M2(R) given by:
T(A)=AN-NA.
(a) Describe bases for the two spaces ker(T), and im(T)
(b) Let x*={11,12,21,22} be the dual basis to the standard basis x={e11,e12,e21,e22} for M2(R).
Describe bases for the two spaces ker(T*), and im(T*).
(c) Determine the rank and nullity of both operators T and T*.
Question 2
(a) Count the number of matrices in M3(Fp) of each rank. Explain.
(b) Count the number of conjugacy classes in M3(F2). Explain.