How do you find the value of #sin ((2pi)/3)#? Trigonometry Trigonometric Identities and Equations Double Angle Identities 1 Answer Shwetank Mauria Jun 27, 2016 #sin((2pi)/3)=sqrt3/2# Explanation: As #sin2A=2sinAcosA# #sin((2pi)/3)=2sin(pi/3)cos(pi/3)# = #2xxsqrt3/2xx1/2# = #1cancel(2)xxsqrt3/2xx1/(1cancel(2))# = #sqrt3/2# Answer link Related questions What are Double Angle Identities? How do you use a double angle identity to find the exact value of each expression? How do you use a double-angle identity to find the exact value of sin 120°? How do you use double angle identities to solve equations? How do you find all solutions for #sin 2x = cos x# for the interval #[0,2pi]#? How do you find all solutions for #4sinthetacostheta=sqrt(3)# for the interval #[0,2pi]#? How do you simplify #cosx(2sinx + cosx)-sin^2x#? If #tan x = 0.3#, then how do you find tan 2x? If #sin x= 5/3#, what is the sin 2x equal to? How do you prove #cos2A = 2cos^2 A - 1#? See all questions in Double Angle Identities Impact of this question 5342 views around the world You can reuse this answer Creative Commons License