Trigonomotery

Question 1

Double angle formulae, sin cos(1,2,3) and tan

Answer 1

1) sin2x= 2sinxcosx
2) Cos2x = 1-2sin^2x
Cos2x = 2cos^2x -1
Cos2x = cos^2x -sin^2x

3) Tan2x = 2tanx/ 1-tan^2x