Question

Prove the following trigonometric identity and show your work: (in other words, show that the identities on the left equal the one on the right). Please show all of your work. cos t (sect−cost) = sin^2t

Answer 1

Cos t (sec t - cos t)
= cos t (1 / cos t - cos t)
= 1 - cos^2 t
= sin^2 t      (using the identity sin^2 t + cos^2 t = 1 )