# TOP 100+ Trigonometric Functions Class 11 MCQ and Answers

Trigonometric Functions Class 11 MCQ and Answers are most important for your upcoming examinations including JEE Main & JEE Advanced. This will help you to score good marks in your exams by helping you to prepare the concepts better and hence, help you to understand the concepts more clearly. This will also give you an idea about how to write answers in a professional manner.

This chapter deals with the application of Trigonometry in different situations. If a person is interested in learning this subject then he/she should definitely read this chapter because it is very useful for them. You can get all the information related to Trigonometry here like what are all the basic concepts of this subject and what are all the formulas used to solve problems related to it.

The main purpose of this article is to provide students with information on how they can easily solve problems when they have very little time left before their exams. They can also learn about different methods which are used by teachers and professors while teaching their students so that they do not have any difficulty studying these topics at home.

## Trigonometric Functions Class 11 MCQ and Answers

1. Find all angles θ such that -2π < θ < 2π and cos θ = √2 / 2

(A) {-7 π / 4, – π / 4 , π / 4 , 7 π / 4}

(B) {- π / 4, – 3 π / 4 , π / 4 , 3 π / 4}

(C) {-5 π / 4, π / 4 , 3 π / 4}

(D) {π / 4 , π / 4 , 3 π / 4}

Answer: {-7 π / 4, – π / 4 , π / 4 , 7 π / 4}

2. If sin t = 1/5 and 0 < t < π/ 2, then cos (4 t) = ?

(A) 0.3464

(B) 0.8

(C) 0.6928

(D) – 0.6928

3. If cos t = 1/3 and 3π /2 < t < 2π in quadrant IV, then sin (4 t) = ?

(A) 8 √2 / 3

(B) – 8 √2 / 3

(C) – 56 √2 / 243

(D) 56 √2 / 81

4. If cos t = 3/4, and sin t < 0, then sin (3 t) = ?

(A) √7 / 16

(B) – 5 √7 / 16

(C) – 3 √7 / 4

(D) 5 √7 / 16

Answer: – 5 √7 / 16

5. If tan x = 5, then tan (2 x) = ?

(A) 10

(B) – 5 / 12

(C) 1 / 10

(D) 5 / 12

6. If cos t = 0.8, then cos (2 t) =?

(A) 0.28

(B) 0.4

(C) 1.0

(D) 1.6

7. If sin t = 0.6 and cot t > 0, then sin (2 t) =?

(A) – 0.96

(B) 0.48

(C) 0.96

(D) – 0.48

8. Which of the following is not correct?

(A) sin(x) = -sin(-x)

(B) sec(-t) = sec(t)

(C) sin(π + x) = sin(x)

(D) cos(π – x) = -cos(x)

Answer: sin(π + x) = sin(x)

9. Which of the following is not the same as tan(t)?

(A) – tan(-t)

(B) tan(t + 2π)

(C) tan(t + π)

(D) tan(t + π / 2)

Answer: tan(t + π / 2)

10. If sin(-t) = 0.54, what is – sin(t) ?

(A) 0.54

(B) -0.54

(C) – 0.46

(D) 0.46

11. In a triangle ABC, cosec A (sin B cos C + cos B sin C) equals

(A) none of these

(B) c/a

(C) 1

(D) a/c

12. The perimeter of a triangle ABC is 6 times the arithmetic mean of the sines of its angles. If the side b is 2, then the angle B is

(A) 30°

(B) 90°

(C) 60°

(D) 120°

13. If cos a + 2cos b + cos c = 2 then a, b, c are in

(A) 2b = a + c

(B) b² = a × c

(C) a = b = c

(D) None of these

Answer: 2b = a + c

14. If tan A – tan B = x and cot B – cot A = y, then the value of cot (A – B) is

(A) x + y

(B) 1/x + y

(C) x + 1/y

(D) 1/x + 1/y

15. If cos a + 2cos b + cos c = 2 then a, b, c are in

(A) 2b = a + c

(B) b² = a × c

(C) a = b = c

(D) None of these

Answer: 2b = a + c

16. The value of 4 × sin x × sin(x + π/3) × sin(x + 2π/3) is

(A) sin x

(B) sin 2x

(C) sin 3x

(D) sin 4x

17. The value of cos 20 + 2sin² 55 – √2 sin65 is

(A) 0

(B) 1

(C) -1

(D) None of these

18. If the angles of a triangle are in the ratio 1 : 4 : 5, then the ratio of the greatest side to the smallest side is

(A) 4 : (√5 – 1)

(B) 5 : 4

(C) (√5 – 1) : 4

(D) none of these

Answer: 4 : (√5 – 1)

19. If 3 × tan(x – 15) = tan(x + 15), then the value of x is

(A) 30

(B) 45

(C) 60

(D) 90

20. The value of cos 5π is

(A) 0

(B) 1

(C) -1

(D) None of these