Question

Simplify and write the trigonometric expression in terms of sine and cosine:
[2+tan^2x/sec^2x]−1=(f(x))^2

Answer 1

break 2 =1+1,
then 1+tan^2 = sec^2
after manipulating, you get cos^2 = f(x)^2 hence, f(x) = cos

Answer 2

thank you!!