The function represents
A periodic but not simple harmonic motion
A simple harmonic motion with a period
A simple harmonic motion with a period half that of
A simple harmonic motion with a period twice that of
x=sin2ωt=12×2sin2ωt
So the particle is executing SHM with amplitude 1/2 and frequency
i.e.
. The equilibrium position of the particle is at x = 1/2.
Now time period of x = cos ωt is
.
So option (3) is right.