Question

Determine whether each of these functions from [a,b,c,d] to itself is one-to-one.
(a) f(a) = b, f(b) = a, f(c) = c, f(d) =d
(b) f(a) = b, f(b) = b, f(c) = d, f(d) = c

Answer 1

a) The function maps distinct elements of its domain to

the function is one-to-one to distinct elements of its codomain.

Answer: the function is one-to-one

b) Since $f(a) = f(b) = b$ , the function is not one-to-one