Exercise:
Prove that if X and Y are in little o n then X bracket Y is also in little o n.
Prove that if X and Y are in little o n then X bracket Y is also in little o n.
Show that X equals 0, 1; 0, 0 and Y equals 0, 0; 1, 0 are in little s l 2 C.
Check that the Jacobi identity holds for the commutator bracket X bracket Y equals X Y minus Y X.
Why is the tangent vector to exp of s X at s = 0 equal to X?