can anyone do this question
The sets A, B and C are given by
A = {1, 2, 3, 4},
A diagram is easy but with a pen
Let see b)
and , so is surjective. But since has more elements than , can't be injective, so can't be bijective.
and , so is surjective. But since has more elements than , can't be injective, so can't be bijective. (yeah the proof is quite similar)
is the identity map on , it is bijective (i.e. injective and surjective).
That means is not injective. Furthermore, as has more elements than , so is not surjective, in conclusion, is "none of these".