Railways PYQCBT 1 2016

RRB NTPC · Question 28

If A + B = 90°, then which of the following is correct? A. sin A = cos B B. sin A + cos B = 0 C. sin A – cos B = 1 D. sin A – cos B = 2

  1. C

  2. A

  3. B

  4. D

Show answer & explanation

Answer: (B) A

Explanation

If A + B = 90°, then B = 90° − A and cos B = cos(90° − A) = sin A.