Lecture 21 (Discrete Math 2020)

A group isomorphism between groups G and H is a function f that is:

1. A.Any bijection between the underlying sets
2. B.A bijection satisfying f(a · b) = f(a) · f(b)
3. C.A function preserving only the identity element
4. D.A surjection that need not be one-to-one