Find the values of the trigonometric functions in Exercises 6 to 10. 
9. sin -11 π / 3

Solution:

We know that the values of sin x repeat after an interval of 360° or 2 π.

It can be written as

sin - 11 π / 3 = sin [ - 11 π /3 + 2 × 2 π ] (to make the angle positive, we are adding the multiples of 2π)

⇒ sin - 11 π / 3 = sin [ - 11 π /3 + 4 π ]

⇒ sin - 11 π / 3 = sin [ (- 11 π + 12 π )/ 3 ]

⇒ sin - 11 π / 3 = sin [ π / 3 ]

⇒ sin - 11 π / 3 = √3/2 (Using trigonometric table)

NCERT Solutions Class 11 Maths Chapter 3 Exercise 3.2 Question 9

Find the values of the trigonometric functions in Exercises 6 to 10. 9) sin -11 π / 3

Summary:

The value of sin - 11π/3 = √3 / 2. We know that the values of sin x repeat after an interval of 360° or 2 π.