Question

A function f is defined as follows: f(x) = 4x + 5, for −4 ≤ x < 0. Find the values of f(−1), f(−2), f(0), if they exist.

Answer 1

f(x) = 4x + 5, – 4 ≤ x < 0
f(–1) = 4(–1) + 5 = –4 + 5 = 1
f(–2) = 4(–2) + 5 = –8 + 5 = –3
x = 0 ∉ domain of f
∴ f(0) does not exist.