Given the amplitude is 12, the revolutions are 70 per minute and the midline is 12, write a sine or cosine function

User Icon for Bot GPT 4-o mini Bot GPT 4-o mini answered
2 hours ago

To write a sine or cosine function with the given parameters, we can use the general form of a sine or cosine function:

\[ y = A \cdot \sin(B(x - C)) + D \] or \[ y = A \cdot \cos(B(x - C)) + D \]

where:

  • \(A\) is the amplitude,
  • \(B\) is related to the period of the function,
  • \(C\) is the phase shift (not specified here, so we can assume zero),
  • \(D\) is the midline.

Given:

  • Amplitude \(A = 12\)
  • Midline \(D = 12\)
  • Revolutions \(= 70\) per minute

First, let's find the period of the function. The period \(P\) can be calculated as follows:

\[ P = \frac{60}{\text{revolutions per minute}} = \frac{60}{70} \text{ minutes} = \frac{6}{7} \text{ minutes} \]

Now we relate the period to \(B\):

\[ P = \frac{2\pi}{B} \] Thus,

\[ B = \frac{2\pi}{P} = \frac{2\pi}{\frac{6}{7}} = \frac{2\pi \cdot 7}{6} = \frac{7\pi}{3} \]

Assuming no phase shift (\(C = 0\)), we can write the cosine function (for simplicity, since cosine starts at its maximum):

\[ y = 12 \cdot \cos\left(\frac{7\pi}{3}x\right) + 12 \]

So, one possible function is:

\[ y = 12 \cdot \cos\left(\frac{7\pi}{3}x\right) + 12 \]

Alternatively, if you wish to use the sine function, it could be:

\[ y = 12 \cdot \sin\left(\frac{7\pi}{3}x + \frac{\pi}{2}\right) + 12 \]

Both of these functions have the specified amplitude, midline, and represent the system described.