How do you find the exact value of sin ((5pi)/3)?

1 Answer
Jul 31, 2016

sin ( (5pi)/3)=-sqrt(3)/2

Explanation:

sin((5pi)/3)=sin(2pi-pi/3)

sin(2pi-pi/3)=-sin(pi/3)

Period of sin is 2pi and 2pi-pi/3 is in the 4th quadrant.
so sin is negative.

sin ((5pi)/3)=sin(2pi-pi/3)=-sin(pi/3)

sin(pi/3)=sqrt(3)/2

so sin ( (5pi)/3)=-sqrt(3)/2