Question

How do you verify the identity `sec^2theta+tan^2theta=sec^4theta-tan^4theta`?

Answer 1

See Below

Explanation:

`RHS: sec^4theta-tan^4theta`

`=(sec^2theta+tan^2theta)(sec^2theta-tan^2theta)`

`=(sec^2theta+tan^2theta)*1`-> use property `1+tan^2theta=sec^2theta`

`=sec^2theta+tan^2theta`

`=LHS`