Skip to main content
Next exam on November 14 – 15, 2026:
All concepts

Function Parity

函数的奇偶性

Definition and tests for even/odd functions: check the domain is symmetric about the origin first, then compare f(−x) with f(x).

Topic drill: learn this step by step, with real exam questions and a mastery check
6 real-exam questions · 5 sittings31 in mock papers28 practice

Formulas

  • Parity Criteria

    Definition
    f(−x)=f(x) (even),f(−x)=−f(x) (odd)f(-x)=f(x)\ \text{(even)},\qquad f(-x)=-f(x)\ \text{(odd)}

    Applies when:Prerequisite: the domain is symmetric about the origin

How the real exam tests it

Questions from real CSCA papers that test this concept. Work each one out before you open the answer.

  1. CSCA Math December 2025 Past Paper
    Which of the following functions is odd?
    • A.y=cos⁡xy=\cos x
    • B.y=x+x3y=x+x^3
    • C.y=x4y=x^4
    • D.y=xsin⁡xy=x\sin x
    Show answer & solution

    Answer: B

    Answer: B For f(x)=x+x3f(x)=x+x^3, f(−x)=−f(x)f(-x)=-f(x), so it is odd. Choose B.
    See it in the full CSCA Math December 2025 Past Paper
  2. CSCA Math June 2026 Past Paper
    Which of the following statements about the odd function y=f(x)y = f(x) is incorrect?
    • A.The domain of the function is symmetric about the origin
    • B.In the domain of the function, f(−x)=f(x)f(-x) = f(x)
    • C.The graph of the function is symmetric about the origin
    • D.In the domain of the function, f(−x)=−f(x)f(-x) = -f(x)
    Show answer & solution

    Answer: B

    For an odd function, both the domain and the graph are symmetric about the origin, so (A) and (C) are true; by definition f(−x)=−f(x)f(-x) = -f(x), so (D) is true. Statement (B) is the property of an even function and is therefore the incorrect statement. Choose (B).
    Take the full CSCA Math June 2026 Past Paper — timed & graded

Real-exam evidence

Recorded past-paper appearances are listed below; online verification is labelled separately.

6 questions across 5 sittings1 of 5 sittings available to verify free online
  • CSCA Math June 2026 Past Paper2 questionsreading page not yet public
  • CSCA Math April 2026 Past Paper1 questionreading page not yet public
  • CSCA Math March 2026 Past Paper1 questionreading page not yet public
  • CSCA Math January 2026 Past Paper1 questionreading page not yet public
  • CSCA Math December 2025 Past Paper1 questionView question 8 and answer free (full paper)

31 questions across 15 mock papers — our own papers, so a coverage signal rather than real-exam evidence

28 related practice questions availablePractise free: FunctionPractise free: Elementary Function

Sitting evidence comes from the CSCA past papers on record; questions whose original paper is missing are excluded, and sprint papers are deliberately not counted.

Glossary

Related concepts