How do you find the value of #cos(pi/3) #?

1 Answer
Alan P.
Sep 19, 2016

#cos(pi/3)=color(green)(1/2)#

Explanation:

Consider an equilateral triangle with sides of length #2#
Since the interior angles are all equal and have a sum of #pi# radians,
each angle is #pi/3#

Dividing the triangle into halves as in the image below
and remembering the definition of #cos# as #("adjacent side")/("hypotenuse")#

We see that #cos(pi/3)=1/2#
enter image source here

Related questions
See all questions in Trigonometric Functions of Any Angle
Impact of this question
65229 views around the world
You can reuse this answer
Creative Commons License