Question

Given that Cos A= 7/ 25 and A lies between 450° and 540° then find Sin A/2 and Cos A/2​

Answer 1

Answer:

Ans : (c) Putting sin (a/4) = x, we get cos(a/2) = 1 - 2x2 and cos a s 2(1 - 2x^2 -1 = 1- «x2 + ... 450° < a < 540° means the angle a/4 lies in the second quadrant, with 112.5° < a ...