How do you find the exact solutions of the equation #4sinxcosx=1# in the interval #[0,2pi)#? Trigonometry Trigonometric Identities and Equations Double Angle Identities 1 Answer salamat Feb 27, 2017 #x = 1/12 pi, 5/12 pi, 13/12 pi and 17/12 pi# Explanation: #4sin x cos x = 1# #2 ( 2 sin x cos x) =1#, where #2sin x cos x = sin 2 x# # 2 sin 2x = 1# #sin 2x = 1/2# #2x =sin^(-1)(1/2)# #2x = 1/6 pi,5/6 pi, 13/6 pi, 17/6 pi# #x = 1/12 pi, 5/12 pi, 13/12 pi and 17/12 pi# 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 10317 views around the world You can reuse this answer Creative Commons License