Question

find the value of cos A/2and sin A/2 give sin A=0.75​

Answer 1

Step-by-step explanation:

For all values of the angle A we know that, cos A = 2 cos^2 A/2 - 1

⇒ 2 cos^2 A/2 = 1 + cos A

⇒ cos^2 A/2 = (1 + cos A)/2

⇒ cos A2 = ± 1+cosA2−−−−−√