How do you evaluate cot (4pi/3)? Trigonometry Right Triangles Trigonometric Functions of Any Angle 1 Answer Rafael Oct 18, 2015 #cot((4pi)/3)=sqrt3/3# Explanation: #(4pi)/3# is a special angle. #cot((4pi)/3)# #=(cos((4pi)/3))/(sin((4pi)/3))# #=[(-1/2)]/[(-sqrt3/2)]# #=(-1/cancel2)*(-cancel2/sqrt3)# #=1/sqrt3*sqrt3/sqrt3# #=color(red)(sqrt3/3)# Answer link Related questions How do you find the trigonometric functions of any angle? What is the reference angle? How do you use the ordered pairs on a unit circle to evaluate a trigonometric function of any angle? What is the reference angle for #140^\circ#? How do you find the value of #cot 300^@#? What is the value of #sin -45^@#? How do you find the trigonometric functions of values that are greater than #360^@#? How do you use the reference angles to find #sin210cos330-tan 135#? How do you know if #sin 30 = sin 150#? How do you show that #(costheta)(sectheta) = 1# if #theta=pi/4#? See all questions in Trigonometric Functions of Any Angle Impact of this question 26075 views around the world You can reuse this answer Creative Commons License