Suppose that n ∈ N and ɸ : {1, 2, . . . , n} → {1, 2, . . . , n}.
a) Prove that ɸ is 1–1 if and only if ɸ is onto.
b) [Pigeonhole Principle] Suppose that E is a finite set and that f : E →E. Prove that f is 1–1 on E if and only if f takes E onto E.
We need at least 10 more requests to produce the solution.
0 / 10 have requested this problem solution
The more requests, the faster the answer.