Question

what is sine 2 pi over 3

Answer 1

in trig, pi is equal to 180 so you substitute it

Answer 2

2(180)/3

360/3

120

sin(120)=.8660

Answer 3

2PI/3 is the same as 2/3 PI. We also know that Pi on the unit circle is 180 degrees, and 2/3 of 180 is 120. On the unit circle its coordinates would be (-1/2, sqrt(3)/2) and the y value is always your sin, so your answer is sqrt(3)/2.