# TOP 100+ Trigonometric Functions Class 11 MCQ Questions and Answers

## Trigonometric Functions Class 11 MCQ Questions and Answers

1. The value of cos² x + cos² y – 2cos x × cos y × cos (x + y) is

(A) sin (x + y)

(B) sin² (x + y)

(C) sin³ (x + y)

(D) sin4 (x + y)

2. The value of (sin 7x + sin 5x) /(cos 7x + cos 5x) + (sin 9x + sin 3x) / (cos 9x + cos 3x) is

(A) tan 6x

(B) 2 tan 6x

(C) 3 tan 6x

(D) 4 tan 6x

3. The value of tan 20 × tan 40 × tan 80 is

(A) tan 30

(B) tan 60

(C) 2 tan 30

(D) 2 tan 60

4. 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)

5. If a×cos x + b × cos x = c, then the value of (a × sin x – b²cos x)² is

(A) a² + b² + c²

(B) a² – b² – c²

(C) a² – b² + c²

(D) a² + b² – c²

Answer: a² + b² – c²

6. The value of cos 180° is

(A) 0

(B) 1

(C) -1

(D) infinite

7. If the sides of a triangle are 13, 7, 8 the greatest angle of the triangle is

(A) ?/3

(B) ?/2

(C) 2?/3

(D) 3?/2

8. The general solution of ?3 cos x – sin x = 1 is

(A) x = n × ? + (-1)n × (?/6)

(B) x = ?/3 – n × ? + (-1)n × (?/6)

(C) x = ?/3 + n × ? + (-1)n × (?/6)

(D) x = ?/3 – n × ? + (?/6)

Answer: x = ?/3 + n × ? + (-1)n × (?/6)

9. If tan² ? = 1 – e², then the value of sec ? + tan³ ? × cosec ? is

(A) 2 – e²

(B) (2 – e²)1/2

(C) (2 – e²)²

(D) (2 – e²)3/2

10. If the radius of the circumcircle of an isosceles triangle PQR is equal to PQ ( = PR), then the angle P is

(A) 2?/3

(B) ?/3

(C) ?/2

(D) ?/6

11. If cos(-t) = 0.34, what is cos(t) ?

(A) -0.34

(B) 0.66

(C) 0.34

(D) – 0.66

12. If 0 < t < ?/2 and sin t = 0.65, what is sin(t + ?) ?

(A) -0.65

(B) 0.65

(C) 0.35

(D) 0.76

13. cos(x) + cos(? – x) =?

(A) 2 cos(x)

(B) cos(x) – sin(x)

(C) cos(x) + sin(x)

(D) 0

14. If tan(t) = 13, then cot(-t) =?

(A) 13

(B) 1 / 13

(C) – 1 / 13

(D) – 13

15. If 0 < t < ? / 2 and sin t = 0.35, then cos(t + ?) =?

(A) 0.94

(B) -0.94

(C) 0.81

(D) -0.81

16. If the point (a, b) is on the Unit Circle associated with the rotation t, then the point on the Unit circle associated with rotation t + ? / 2, has the following coordinates

(A) (b, a)

(B) (-b, a)

(C) (-b, -a)

(D) (-a, b)

17. If the point (a, b) is on the Unit Circle associated with the rotation t and point (c, d) is also on the Unit circle associated with rotation t + ?, then which of the following is correct?

(A) c = – a and d = – b

(B) c = – a and d = b

(C) c = a and d = b

(D) c = a and d = – b

Answer: c = – a and d = – b

18. If point (a , b) is on the Unit Circle associated with the rotation t, which of the following is not correct?

(A) sin(t) = b

(B) cos(t) = a

(C) sin(-t) = – a

(D) cos(-t) = – a

19. Find the point on the Unit Circle associated with the angle 5?/3

(A) (1 / 2 , 1 / 2)

(B) (-?3 / 2 , 1/2)

(C) (1 / 2 , -?3 / 2)

(D) (-?3 / 2 , -1/2)

Answer: (1 / 2 , -?3 / 2)

20. Find the point on the Unit Circle associated with the rotation -9?/2

(A) (0 , -1)

(B) (0 , 1)

(C) (1 , 0)

(D) (-1 , 0)