Question

Cos A=2 , find the value of sin A and tan A in details

Answer 1

Answer:

Step-by-step explanation:

How to express sin A/2, cos A/2 and tan A/2 in terms of cos A?

(i) 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−−−−−√