REALLY NEED HELP PLEASE!!!!
PROBLEM: If cos(t) = -3/5 where pi

Question

REALLY NEED HELP PLEASE!!!!
PROBLEM:  If cos(t) = -3/5 where pi<t<3pi/2, find the values of the following trigonometric functions:
cos(2t) =
sin(2t) =
cos(t/2) =
sin(t/2) =

NOTE:  Give exact answers, do not use decimal numbers.  The answer should be a fraction or an arithmetic expression.  If the answer involves a square root it should be entered as sqrt; e.g. the square root of 2 should be written sqrt(2).

anonymous · Answer

based on given info, we'll get sin t= -4/5, tan t= 4/3.
cos (2t) = 2 cos^2 (t) -1 
sin(2t)= 2 sin t cos t
just you half angle formulae to solve cos (t/2) and sin (t/2)

help · Answer

Nope, wrong.  Thanks anyways