Express the function f : X → R given by f(x) = x3 + 1 as set of ordered pairs, where X = {–1, 0, 3, 9, 7}.
Given X = {–1, 0, 3, 9, 7}
f : X → R and f(x) = x3 + 1
When x = –1, we have f(–1) = (–1)3 + 1
⇒ f(–1) = –1 + 1
∴ f(–1) = 0
When x = 0, we have f(0) = 03 + 1
⇒ f(0) = 0 + 1
∴ f(0) = 1
When x = 3, we have f(3) = 33 + 1
⇒ f(3) = 27 + 1
∴ f(3) = 28
When x = 9, we have f(9) = 93 + 1
⇒ f(9) = 729 + 1
∴ f(9) = 730
When x = 7, we have f(7) = 73 + 1
⇒ f(7) = 343 + 1
∴ f(7) = 344
Thus, f = {(–1, 0), (0, 1), (3, 28), (9, 730), (7, 344)}