Phasors
$ x(t)=Ae^{j\theta+\phi} $
Where A is the radius of the phasor and $ \phi $ if the offset.
Useful Phasors Facts
$ e^{j\theta} = \cos{\theta}+j\sin{\theta} $
$ Ae^{j[\theta+\phi]}=Ae^{j\theta}e^{j\phi} $
$ \cos{\theta}=\frac{e^{j\theta}+e^{-j\theta}}{2} $
