Evaluate (if possible) the sine, cosine, and tangent of the real number. (If not possible, enter IMPOSSIBLE.) t = - 5p/4 .

Evaluate the trigonometric function using its period as an aid.
cos (-5p/2).

Use the value of the trigonometric function to evaluate the indicated functions.
sin(–t) = 3/8
(a) sin(t)
(b) csc(t)

Can someone please explain to me how we these types of equations?

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