Show that the following are equivalent:
(A) If I is a nil ideal in any ring R, then Mn(I) is nil for any n.
(B)' If I is a nil ideal in any ring, then M2(I) is nil.
Show that from Kothe’s Conjecture (“The sum of two nil left ideals in any ring is nil”.) followsthe statement:
if I is a nil ideal in any ring R, then Mn(I) is nil for any n.