How do you express amplitude, frequency and phase modulation?

Explanation

The equation of a carrier wave may be expressed
as ` e = E sin (omegat + phi)`
where e is instantaneous voltage at time `t , omega` is
angluar frequency and `phi` is the phase w.r.t. some
refrence. By varying E, we get amplitude
modulation. By varying `omega`, we get frequency
modulation and by varying `phi`, we get phase
modulation.