Homework Statement
Suppose that |A| = n and |B| = m with n ≤ m. How many one-to-one functions f are possible with f: A → B?
Homework Equations
If |A| = |B| = m how many different bijections f: A → B are possible?
Answer: m!
The Attempt at a Solution
I really do not know how to start off...
Firstly, I apologize if this is the wrong section to post, not sure where in homework help for logic is suppose to be post.
Otherwise, I have no idea how to approach this problem, I just make an equation and hope and pray it matches the results of S, or try and keep adding statements to bring...