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Grade 11 · Trigonometry
Trig Identities & Reduction Formulae: Full Guide
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Name:
Class:
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Mark
/ 20
Answer all questions. Show all your working — marks are awarded for method as well as the final answer.
- 1Simplify sinθ · tanθ · cosθ. (simplify)(2)
- 2Simplify (1 − sin2θ). (identity)(2)
- 3Simplify cos2θ ⁄ (1 − sin2θ). (identity)(2)
- 4Prove tanθ · cosθ = sinθ. (prove)(2)
- 5In which quadrant are only sine positive? (CAST)(2)
- 6sinθ = 0,5, θ in Q2. Is cosθ + or −? (CAST)(2)
- 7Simplify cos(180° − θ). (reduction)(2)
- 8Simplify sin(360° − θ). (reduction)(2)
- 9Exact value of sin 150°. (exact)(2)
- 10Exact value of cos 210°. (exact)(2)
TOTAL: 20 marks