Question

Let A = [9, 10, 11, 12, 13] and let f : A → N be defined by f(n) = the highest prime factor of n. Find the range of f.

Answer 1

Given:
A ={9, 10, 11, 12, 13}
f : A → N be defined by f (n) = the highest prime factor of n.
f (9) = the highest prime factor of 9 = 3
f (10) = the highest prime factor of 10 = 5
f (11) = the highest prime factor of 11 = 11
f (12) = the highest prime factor of 12 = 3
f (13) = the highest prime factor of 13 = 13
The range of f is the set of all f (n), where $n\in A$.
Therefore,
range of f = {3, 5, 11, 13}