Basics of Periodic Functions

Make sure you know how to switch between radian measure and degree measure on your calculator of choice. These exercises are designed in terms of radian measure.

  1. For what angle \(t\) between \(-\tfrac{\pi}{2}\) and \(\tfrac{\pi}{2}\) does \(\sin(t) = 0.777?\)
  2. For what angle \(t\) between \(0\) and \(\pi\) does \(\cos(t) = 0.314?\)
  3. Is there an angle \(t\) such that \(\sin(t) = 2.3?\) If so, what it is? If not, why not?
  4. First sketch the graph of \(\sin(x)\) for reference. Then graph each of the following functions, thinking of them as a transformation of the sine function.

    \(\displaystyle 2\sin\bigl(x\bigr) \)
    \(\displaystyle \sin\bigl(2x\bigr) \)
    \(\displaystyle \sin\bigl(x+2\bigr) \)
    \(\displaystyle \sin\bigl(x\bigr)+2 \)
    \(\displaystyle \sin\bigl(x+\tfrac{\pi}{6}\bigr) \)
    \(\displaystyle \tfrac{1}{3}\sin\bigl(4x\bigr) \)
    \(\displaystyle 5\sin\bigl(\tfrac{1}{2}x\bigr) \)
    \(\displaystyle \sin\bigl(x-\tfrac{\pi}{3}\bigr)-1 \)
    \(\displaystyle \sin\bigl(\tfrac{1}{3}(x+\tfrac{\pi}{4})\bigr) \)
  5. With regards to each of the transformations in the previous exercise, affirm the meaning of the vocabulary terms period, amplitude, and phase shift.
  6. Each of the following plots feature the graph of a transformation of the cosine function. First sketch the graph of \(\cos(x)\) for reference. Then write down the formulas for the functions graphed below thinking of them as a transformation of the cosine function.