Question

Question #f14bb

Answer 1

`+- 4/5`

Explanation:

Use trig identity:
`sin^2 x = 1 - cos^2 x`
`sin^2 (2t) = 1 - cos^2 (2t) = 1 - 9/25 = 16/25`
`sin (2t) = +- 4/5`
Because `cos (2t) = 3/5` is positive, on the unit circle, 2t is either in quadrant I or Quadrant IV.
Sin (2t) may be either positive or negative, depending on value of t.