Solve the Problem $y = \sin 2 \pi l t + \sin 2 \pi h t$

question 65

Multiple Choice

Solve the problem.
-The sound produced by touching each button on a touch-tone phone is described by $y = \sin 2 \pi l t + \sin 2 \pi h t$
where $l$ and $h$ are the low and high frequencies (cycles per second) in the figure shown.


Touch-Tone phone
Describe the sound emitted by touching the 0 key as a product of sines and cosines.

• A) \(\mathrm { y } = 2 \sin ( 2277 \pi \mathrm { t } ) \cos ( 395 \pi \mathrm { t } )\)
• B) \(\mathrm { y } = 2 \sin ( 2418 \pi \mathrm { t } ) \cos ( 536 \pi \mathrm { t } )\)
• C) \(\mathrm { y } = 2 \sin ( 395 \pi \mathrm { t } ) \cos ( 2277 \pi \mathrm { t } )\)
• D) \(\mathrm { y } = 2 \sin ( 536 \pi \mathrm { t } ) \cos ( 2418 \pi \mathrm { t } )\)

---

Definitions:

Close Substitutes

Products or services that can serve as almost identical alternatives to one another, typically influencing consumer choice and market dynamics.

Monopoly

A market structure characterized by a single seller dominating the market, often resulting in limited competition and higher prices for consumers.

Patent

A legal document granting an inventor exclusive rights to produce, use, and sell their invention for a certain period of time.

Exclusive Right

A legal provision that allows only the holder to perform a specific activity or use a particular property.