Question

if √3 cot A=3 then find the value of cos 2a​

Answer 1

Answer:

cot A = 3/√3

=> cot A = √3

=> cot A = cot 30°

On comparing LHS and RHS of above equation,

Angle A = 30°

=> 2A = 60°

=> cos 2A = cos 60°

=> cos 2A = 1/2