Trigonometry (Railway Maths) (Part – V)

Total Questions: 50

11. The minimum value of 9 sin²θ + 10 cos²θ is: [RRB NTPC 09/03/2021 (Evening)]

Correct Answer: (d) 9
Solution:

12. If 2xy cosθ + (x² - y²) sinθ = x² + y², then the value of tanθ is: [RRB NTPC 09/03/2021 (Evening)]

Correct Answer: (c) (x² - y²) / 2xy
Solution:

13. tan 100° + tan 125° + tan 100° + tan 125° is equal to: [RRB NTPC 11/03/2021 (Morning)]

Correct Answer: (b) 1
Solution:

14. Solve the given equation. sin 21° cos 9° - cos 84° cos 6° = ? [RRB NTPC 11/03/2021 (Morning)]

Correct Answer: (b) 1/4
Solution:

15. sinα = 1/√5 and cosβ = 3/√10, then find the value of α + β [RRB NTPC 12/03/2021 (Morning)]

Correct Answer: (b) 45°
Solution:

16. If sinθ + cosθ = 1, then the value of tan 2θ is: [RRB NTPC 12/03/2021 (Morning)]

Correct Answer: (d) 0
Solution:

17. Find the value of sin34° + cos64° - cos4°. [RRB NTPC 12/03/2021 (Evening)]

Correct Answer: (d) 0
Solution:

18. If sinθ + cosθ = p and secθ + cosecθ = q, then the value of q(p² - 1) is. [RRB NTPC 13/03/2021 (Morning)]

Correct Answer: (c) 2p
Solution:

19. In the triangle ABC, a = 25, b = 45, and c = 30. The value of cosA is: [RRB NTPC 13/03/2021 (Evening)]

Correct Answer: (d) 23/27
Solution:

20. If sinA = 4/√17, then tan2A = ? (0° < A < 90°) [RRB NTPC 14/03/2021 (Morning)]

Correct Answer: (b) -8/15
Solution: