y = 2x + 1
When x = 1 ⇒ y = 2(1) + 1 = 2 + 1 = 3
When x = 2 ⇒ y = 2(2) + 1 = 4 + 1 = 5
When x = 3 ⇒ y = 2(3) + 1 = 6 + 1 = 7
When x = 4 ⇒ y = 2(4) + 1 = 8 + 1 = 9
When x = 5 ⇒ y = 2(5) + 1 = 10 + 1 = 11
f = {(1,3) (2, 5) (3, 7) (4, 9) (5, 11)}
(a) Arrow diagram

(b) A graph

(c) Roster form: R = {(1,3) (2,5) (3,7) (4,9) (5,11)}