​ If sec θ + tan θ = p, then prove that sin θ = p^2 -1 / p^2 +1

Question

If sec θ + tan θ = p, then prove that sin θ = \(\frac{p^2-1}{p^2+1}\)

Answer 1

sec θ + tan θ = p 

sec² θ – tan² θ = 1 

(sec θ + tan θ) (sec θ – tan θ) = 1

p. (sec θ – tan θ) = 1