Trig
posted by Sara on .
Find sin2theta, cos2theta if csctheta=13/12 and lies in quadrant II.
Thank you!

If csc Ø = 13/12, the sinØ = 12/13
so we are dealing with the 12513 rightangled triangle in II
then cosØ = 5/13
sin 2Ø = 2sinØcosØ
= 2(12/13)(5/13)
= 120/169
cos 2Ø = cos^2 Ø  sin^2 Ø
= 25/169  144/169
= 119/169