MCQ Practice Question
An analog multiplier whose output is proportional to Vx times Vy can be used as a frequency doubler by applying the same sinusoid to both inputs because sin^2(theta) contains?
Correct Answer: A. A DC term and a component at twice the input frequency
Explanation: sin²(theta)=[1-cos(2theta)]/2, so squaring a sinusoid produces a DC term and a second-harmonic component.
Reference: Standard analog electronics: analog multiplier
