Functions & Graphs is one of 9 topics in the Grade 12 Technical Mathematics CAPS syllabus, covered across 3 lessons on Study Vault. Below are real practice questions from this topic with full worked answers.
Sample practice questions
Easy
1. If f(x) = 3x - 2, find f(5).
Answer: 13 — f(5) = 3(5) - 2 = 15 - 2 = 13.
Easy
2. What does the domain of a function refer to?
The complete set of valid input (x) values
The complete set of output (y) values only
The single largest y-value on the graph
The y-intercept of the graph
Answer: The complete set of valid input (x) values — The domain is the complete set of input (x) values for which a function is defined.
Medium
3. State the value of x that must be excluded from the domain of f(x) = 1/(x - 5).
Answer: 5 — The denominator cannot equal zero, so x - 5 cannot equal 0, meaning x = 5 must be excluded from the domain.
