Trigonometric Identities – Double Angle, Half Angle, Product-to-Sum

Grade 11 Maths Higher — Trigonometric Identities – Double Angle, Half Angle, Product-to-Sum: 25 practice questions with instant scoring and explanations.

1. sin 2A =
2. cos 2A =
3. tan 2A =
4. sin(A/2) =
5. cos(A/2) =
6. tan(A/2) =
7. sin A · sin B =
8. cos A · cos B =
9. sin A · cos B =
10. sin 120° =
11. If sin θ = 3/5 and θ is acute, then sin 2θ =
12. cos 120° =
13. If tan θ = 1/2, then tan 2θ =
14. sin 22.5° =
15. The identity 1 + cos 2A =
16. The identity 1 - cos 2A =
17. sin 2A/(1 + cos 2A) =
18. If cos A = 3/5 (A in first quadrant), then cos 2A =
19. tan 15° =
20. cos A + cos B =
21. sin A - sin B =
22. sin²A - sin²B =
23. If A = 30°, then sin 2A - cos 2A =
24. tan(A/2) in terms of sin A and cos A is:
25. sin 3A = 3 sin A - 4 sin³A is equivalent to: