Question

2cos=
how to make this sum​

Answer 1

Step-by-step explanation:

Cos (A + B) + Cos (A - B) = 2 Cos A Cos B (The term Sin A Sin B is cancelled due to the opposite sign). Therefore, the formula of 2 Cos A Cos B is given as: 2 Cos A Cos B = Cos (A + B) + Cos (A - B)