Variation 1 · answer guide
Trigonometric identity — Frequencies 4 and 2
Question
Evaluate .
This practice question was inspired by Question 12(d) in the 2020 NSW HSC Mathematics Extension 1 examination, © NESA. It is an original TestMum variation that practises the same mathematical idea, not an official NESA question.
Step by step
- Set up the solution: apply the named identity first and simplify before integrating or solving..
- Finish the calculation, then check that the result meets the question’s conditions.Integrate: .
- State the final answer clearly in the form the question requested.Value: .
Common mistake: changing so many features that the new example no longer tests the same mathematical idea.
Verification: Arithmetic: upper , lower , half of is .
Any mark labels are a TestMum study aid, not an official NESA marking allocation.
← Back to 2020 HSC Extension 1 paper Question 12(d)