$$v\left(t\right)\;=5\left[\cos\left(10^6\mathrm{πt}\right)\;-\;\sin\left(10^3\mathrm{πt}\right)\times\sin\left(10^6\mathrm{πt}\right)\right]$$ represents

The response of an LCR circuit to a step input is
(a) Over damped
(b) Critically damped
(c) Oscillatory

If the transfer function has

(1) poles on the negative real axis
(2) poles on the imaginary axis
(3) multiple poles on the positive real axis
(4) poles on the positive real axis
(5) multiple poles on the negative real axis

Tachometer feedback in a d.c. position control system enhances stability.

The poles of a continuous time oscillator are ___________.