3. {3,} Consider the function f : IR } Rdened by f($) = [ITl]. Let S = {3: E IR: 1 5: r if. E}, and T = {2}. In the box below, write the values of f[S) and f _1(T} {b} Let A, and B he sets, with IAI = 3 and |B| = 2. How n'isn},F of all the possible function f : A ) B are onto1 and how many are injections? Write your answer in the box below. The number of onto functions is ...... The number of injective functions is . ..... (c) In the box below, prove that if n. E 3+ is odd, then n2 E 1 (mod 3). Proof