Question 895978
Using this unit circle


<img width = 500 src = "http://upload.wikimedia.org/wikipedia/commons/4/4c/Unit_circle_angles_color.svg">


(Image Source: Wikipedia  <a href="http://en.wikipedia.org/wiki/File:Unit_circle_angles_color.svg">http://en.wikipedia.org/wiki/File:Unit_circle_angles_color.svg</a> )


we see that at the angle {{{pi/3}}} we have the point *[Tex \Large \left(\frac{1}{2}, \frac{\sqrt{3}}{2}\right)] (look at the 60 degree angle)


The x coordinate of this point is equal to {{{cos(pi/3)}}}


So, {{{cos(pi/3)=1/2}}}



The y coordinate of this point is equal to {{{sin(pi/3)}}}


So, {{{sin(pi/3)=sqrt(3)/2}}}