Question

If cos²A-sin²A= 1/2 then tan²A=?​

Answer 1

Answer:

Cos²A - Sin²A = 1/2

=> Cos 2A = 1/2 [ ∵ Cos2A = Cos²A - Sin²A]

=> Cos2A = Cos 60°

=> 2A = 60°

=> A = 30°.

Now, Tan²A = Tan²(30°)

= (1/ root 3)² = 1/3.