Posted by Stephanie823 on .
Use one of the identities
cos(t + 2ðk) = cos t or sin(t + 2ðk) = sin t to evaluate each expression. (Enter your answers in exact form.)
(a)
sin(17ð/4)
(b)
sin(−17ð/4)
(c)
cos(17ð)
(d)
cos(45ð/4)
(e)
tan(−3ð/4)
(f)
cos(7ð/4)
(g)
sec(ð/6+2ð)
(h)
csc(2ð −ð/3)

Pre Calculus 
Reiny,
look at my answer to Kaleen
http://www.jiskha.com/display.cgi?id=1331432278
the questions are similar.