Musical notes are classified by frequency. The note middle C has a frequency of 262 hertz. The note C above middle C has a frequency of 524 hertz. The note C below middle C has a frequency of 131 hertz. 1) Write an equation of the sine function that represents middle C if its amplitude is 0.2.

2)Write an equation of the sine function that represents C above middle C if its amplitude is one half that of middle C.

3)Write an equation of the sine function that represents C below middle C if its amplitude is twice that of middle C.

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  1)  f(t) = 0.2·sin(524π·t)

  2)  f(t) = 0.1·sin(1048π·t)

  3)  f(t) = 0.4·sin(262π·t)

Step-by-step explanation:

The general form of the desired equation is ...

  f(t) = A·sin(2πf·t)

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1) f = 262; A = 0.2

  f(t) = 0.2·sin(524π·t)

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2) f = 524; A = 0.1

  f(t) = 0.1·sin(1048π·t)

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3) f = 131; A = 0.4

  f(t) = 0.4·sin(262π·t)

answer:   28.56 feet (approx)

step-by-step explanation:

since, triangle abc has measure of angle c equal to 55 degrees, measure of angle abc equal to 90 degrees, and length of bc equal to 20 feet.

we have to find out the measurement of segment ab.

therefore, tan 55° =

but bc = 20 feet.

⇒ tan 55 ° =  

⇒ ab = 20 × tan 55 °

⇒ ab = 20 × 1.42814800674

⇒ ab = 28.5629601348   ≈ 28.56 feet