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Solve the following equation, giving the exact solutions which lie in [0, 2π). (Enter your answers as a comma-separated list.)
sin(2x) = sin(x)

Respuesta :

sin(2x)=2sin(x)cos(x) -->(trigonometric identities)
2sin(x)cos(x)=sin(x)
divide by sin(x)
2cos(x)=1
cos(x)=1/2
arccos(1/2)= pi/3, 4pi/3

The exact solutions which lie in [0, 2π).

[tex]0,\:\pi ,\:\frac{\pi }{3},\:\frac{5\pi }{3}[/tex]

Given :

[tex]sin(2x)=sin(x)[/tex]

the exact solutions which lie in [0, 2π)

Subtract sin(x) from both sides

[tex]\sin \left(2x\right)-\sin \left(x\right)=0\\\\sin(2x)= 2 sinx cosx \\2sinxcosx-sinx=1\\factor \; out \;sin(x)\\\sin \left(x\right)\left(2\cos \left(x\right)-1\right)=0\\[/tex]

Set each factor =0 and solve for x

[tex]\sin \left(x\right)=0\quad \mathrm{or}\quad \:2\cos \left(x\right)-1=0\\sin(x)=0, x=0,\:x=\pi \\\\2cos(x)-1=0\\2cos(x)=1\\cos(x)=\frac{1}{2} \\x=\frac{\pi }{3},\:x=\frac{5\pi }{3}[/tex]

Exact solutions for the given equation is

[tex]0,\:\pi ,\:\frac{\pi }{3},\:\frac{5\pi }{3}[/tex]

Learn more : brainly.com/question/5093486