Value of Trigonometric Functions at Multiples and Submultiples of an angle – Exercise 9.2 Solutions

1. Prove that: sin 5x = 5 sin x – 20 sin³ x + 16 sin⁵ x  Watch Solution
2. Prove that: 4 (cos³ 10° + sin³ 20°) = 3 (cos 10° + sin 20°) Watch Solution
3. Prove that: cos³ x sin 3x + sin³ x cos 3x = 3/4 sin 4x Watch Solution
4. Prove that: tan x tan (x + π/3) + tan x tan (x – π/3) + tan (x + π/3) tan (x – π/3) = – 3 Watch Solution
5. Prove that: tan x + tan (π/3 + x) – tan (π/3 – x) = 3 tan 3x Watch Solution
6. Prove that: cot x + cot (π/3 + x) – cot (π/3 – x) = 3 cot 3x Watch Solution
7. Prove that: cot x + cot (π/3 + x) + cot (2π/3 + x) = 3 cot 3x Watch Solution
8. Prove that: sin 5x = 5 cos⁴ x sin x – 10 cos² x sin³ x + sin⁵ x Watch Solution
9. Prove that: sin³ x + sin³ (2π/3 + x) + sin³ (4π/3 + x) = –3/4 sin 3x. Watch Solution
10. Prove that: |sin x sin (π/3 – x) sin (π/3 + x)| ≤ 1/4 for all values of x. Watch Solution
11. Prove that: |cos x cos (π/3 – x) cos (π/3 + x)| ≤ 1/4 for all values of x. 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