How Well Do You Know Trig. Identities?

1 Tan squared U

(Sec squared U) - 1 (Sec squared U) + 1

Cos U Sin U

- Sin U Sin U

(Cos U)(Cos V) - (Sin U)(Sin V) (Sin U)(Cos V) + (Cos U)(Sin V)

2(Cos U) - 1 2(Sin U)(Cos U)

(1 + Cos(2U)) / 2 (Cos (2U)) / 2

- Cot U 1 - Tan U

- Tan U Tan U

- 2 (Sin ((U + V) / 2))(Sin ((U - V) / 2)) 2 (Cos ((U + V) /2))(Sin ((U + V) / 2 ))