Solving Sin(2x)+Sin(x)=0 over [0,2π)

[RansidMeat]

hello there,
how do i solve over [0,2pi) for sin(2x)+sin(x)=0
thanks for what help you can give
RansidMeat

 

[cookiemonster]

Yay, problem solved.

cookiemonster

 

[AKG]

hello there,
how do i solve over [0,2pi) for sin(2x)+sin(x)=0
thanks for what help you can give
RansidMeat

sin(2x) + sin(x) = 0
2sin(x)cos(x) + sin(x) = 0
2sin(x)cos(x) = -sin(x)
2cos(x) = -1 OR sin(x) = 0
cos(x) = -0.5 OR x = 0, pi
x = 2pi/3, 4pi/3 OR x = 0, pi
x = 0, (2/3)pi, pi, (4/3)pi.