Answer:
- sin = -√3/2
- cos = -1/2
- tan = √3
- sec = -2
- csc = (-2/3)√3
- cot = (√3)/3
Explanation:
See the attached picture for a drawing of the angle and its terminal point coordinates. Those are (cos(4π/3), sin(4π/3)), so we have the following trig function values:
sin(4π/3) = -√3/2
cos(4π/3) = -1/2
tan(4π/3) = sin/cos = √3
sec(4π/3) = 1/cos = -2
csc(4π/3) = 1/sin = -(2√3)/3
cot(4π/3) = 1/tan = (√3)/3
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Additional comment
It helps to know that 1/√a = (√a)/a. This lets you write the ratios with a rational denominator in each case.