You should find the standard form of a cosine curve in your text or in your notes.
for y = a cos (kØ) ,
the amplitude is |a| and
the period is 2π/k in radians or 360°/k in degrees
so you have y = (1/4)cos (2π/3 Ø)
your amplitude is correct
period = 2π/(2π/3)
= 2π(3/(2π)) = 3 radians
I will assume that by the "midline" you mean the Ø axis.
You should really study and memorize the basic cosine curve.
A sound wave is modeled with the equation . y=1/4cos 2pi/3treta
a. Find the period. Explain your method.
b. Find the amplitude. Explain your method.
c. What is the equation of the midline? What does it represent?
A- The period can not be found because there is no time in the equation.
B- Amplitude will be 1/4. I don't know exactly how to explain it...
C- I don't know about c , I need help
2 answers
yeah but I can't type "Ø" unless i copy and paste it , Thanks though
1 answer