Question

I need solution pls.. any one help me ​

Answer 1

take 1=sin²A/2+cos²A/2 and

cos A = cos 2 (A/2)

= cos²A/2- sin²A/2

after substitution you will get cot A/2

Answer 2

Answer:

take 1=sin²A/2+cos²A/2 and

cos A = cos 2 (A/2)

= cos²A/2- sin²A/2

after substitution you will get cot A/2