sec square theta - tan square theta = 1

Answer 1

sec^2 θ - tan^2 θ = 1
What are we doing? Solving for θ ?
or proving it is an identity?

you should know the important identity: tan^2 θ + 1 = sec^2 θ

LS = sec^2 θ - (sec^2 θ - 1)
= ....