Value of Trigonometric Functions at Multiples and Submultiples of an angle – Exercise 9.3 Solutions

1. Prove that: sin² 2π/5 – sin² π/3 = (√5 – 1)/8  Watch Solution
2. Prove that: sin² 24° – sin² 6° = (√5 – 1)/8 Watch Solution
3. Prove that: sin² 42° – cos² 78° = (√5 + 1)/8 Watch Solution
4. Prove that: cos 78° cos 42° cos 36° = 1/8 Watch Solution
5. Prove that: cos π/15 cos 2π/15 cos 4π/15 cos 7π/15 = 1/16 Watch Solution
6. Prove that: cos 6° cos 42° cos 66° cos 78° = 1/16 Watch Solution
7. Prove that: sin 6° sin 42° sin 66° sin 78° = 1/16 Watch Solution
8. Prove that: cos 36° cos 42° cos 60° cos 78° = 1/16 Watch Solution
9. Prove that: sin π/5 sin 2π/5 sin 3π/5 sin 4π/5 = 5/16 Watch Solution
10. Prove that: cos π/15 cos 2π/15 cos 3π/15 cos 4π/15 cos 5π/15 cos 6π/15 cos 7π/15 = 1/128 Watch Solution

Chapter 9: Values of Trigonometric Functions at Multiples and Submultiples of an Angle – R. D. Sharma Class 11th Maths

1. Values of Trigonometric Functions at Multiples and Submultiples of an Angle Exercise 9.1 Video Solution

2. Values of Trigonometric Functions at Multiples and Submultiples of an Angle Exercise 9.2 Video Solution

3. Values of Trigonometric Functions at Multiples and Submultiples of an Angle Exercise 9.3 Video Solution

4. Values of Trigonometric Functions at Multiples and Submultiples of an Angle Multiple Choice Questions (MCQs) Video Solution Video Solution

5. Values of Trigonometric Functions at Multiples and Submultiples of an Angle Fill in the Blanks (FBQs) Video Solution

6. Values of Trigonometric Functions at Multiples and Submultiples of an Angle Very Short Answer Questions (VSAQs) Video Solution Video Solution