Using the unit circle, how do you find the value of the trig function: tan pi/6?

1 Answer
Oct 7, 2015

Find tan (pi/6) on the trig unit circle

Ans: #(sqrt3)/3#

Explanation:

On the trig unit circle, M being the terminal point of the arc #(pi/6)#
#AT = tan (pi/6)# (by definition)
OM = OA = R = 1 (definition of trig unit circle)
#Mm = (OM)/2 = 1/2# (equilateral triangle)
#Om = sqrt3/2# (height of equilateral triangle)

Triangle OAT and triangle OMm
#(AT)/(Mm) = (OA)/(Om) #--> #AT = (Mm)((OA)/(Om))#
#tan (pi/6) = (1/2)(1/(sqrt3/2)) = (1/2)(2/sqrt3) = 1/(sqrt3) = (sqrt3)/3#
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