College Algebra CLEP Prep 2026 – 400 Free Practice Questions to Pass the Exam

The domain of a function includes all possible input values. In this case, the function f(x) = 2x +3 has an unrestricted domain, meaning it includes all real numbers. Options B, C, and D are incorrect because they are not inclusive of all possible input values. Option B only includes whole numbers, while options C and D only include a subset of whole numbers (prime and non-prime numbers). Therefore, A is the correct and complete representation of the domain for this function.