Evaluate (if possible) the sine, cosine, and tangent at the real number t. (If an answer is undefined, enter UNDEFINED.) t = − 2π 3 sin t = cos t = tan t =

Question

Evaluate (if possible) the sine, cosine, and tangent at the real number t. (If an answer is undefined, enter UNDEFINED.)

t = − 2π

3

 

sin t	=
cos t	=
tan t	=

Answer 1

-2pi/3 = -2 pi/3 * 180/pi = -120 = 240

that's quadrant 3 where sine and cosine are negative

and tangent is positive...

the characteristic angle is 60degress past the negative x-axis

so sine is =-sqrt(3)/2

cosine is -1/2

tangent is sqrt(3)

MS Excel agrees: