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Subsection 3.1 Inverse Trigonometric Functions Exercises

  1. Suppose that \(\sin \alpha = \frac{\sqrt{3}}{2}\text{.}\) Use Desmos to help you find possible value(s) of \(\alpha\text{,}\) where \(0 \leq \alpha \leq \frac{\pi}{2}\text{.}\)
  2. Let \(\cos \theta = .75\text{.}\)
    1. Find \(\theta\) if \(\theta\) is a positive angle in the first quadrant.
    2. Find \(\theta\) if \(\theta\) is a positive angle in the fourth quadrant.
  3. Suppose that \(\triangle DEF\) is a right triangle, with right angle at \(E\text{.}\) Let \(DE=5\) and \(EF=3\text{.}\) Determine \(DF\text{,}\) and then use the side lengths to compute \(\sin \angle D\text{,}\) \(\cos \angle D\text{,}\) and \(\tan \angle D\text{.}\)
  4. Suppose that \(\triangle KLM\) is a right triangle, with right angle at \(L\text{.}\) Let \(KM=8\text{,}\) and let \(\angle MKL = .25\) radians. Find the lengths \(KL\) and \(LM\text{.}\)
  5. A circle has its center at \(C= (3, 5)\text{,}\) and just touches the \(y\)-axis.
    1. Draw a diagram of the circle in the \(xy\)-plane.
    2. Write the equation of the circle.
    3. Find the circumference and area of the circle.
    4. Find the length of the arc of the circle cut out by an angle of \(\frac{\pi}{6}\) radians.
    5. Find the area of the sector of the circle cut out by an angle of \(\frac{\pi}{6}\) radians.
    6. Find the coordinates of point \(A\text{,}\) if point \(A\) is in the 2 o’clock position on the circle.
  6. A circle has its center at \(V=(6, 0)\text{,}\) and contains the point \((0,0)\text{.}\)
    1. Draw a diagram of the circle in the \(xy\)-plane.
    2. Write the equation of the circle.
    3. Find the circumference and area of the circle.
    4. Find the length of an arc of the circle cut out by an angle of \(\frac{5\pi}{6}\text{.}\)
    5. Find the coordinates of the point \(B\text{,}\) if ray \(\overrightarrow{VB}\) makes an angle of \(\frac{\pi}{4}\) with the \(x\)-axis (there are multiple answers).
    6. What is the measure of \(\angle FVP\text{,}\) where \(F=(9, 3\sqrt{3})\) and \(P=(12,0)\text{?}\)
  7. The owners of a small concert venue (capacity 1050) have determined that the number of people who attend is a function of the price of the tickets. If tickets are sold for $3, the venue will sell out. On the other hand, at $38/ticket, no one will buy tickets.
    1. Assuming that the number of tickets sold, \(S(t)\text{,}\) is a linear function of the price, \(t\text{,}\) write an equation for \(S(t)\text{.}\)
    2. Write an equation for the income the theater will generate, \(g(t)\text{,}\) as a function of the ticket price, \(t\text{.}\)
    3. What is the maximum amount of money that the theater can earn? What price should they charge, and how many people will come at this price?
  8. The power produced by a windmill (in watts) is given by the equation
    \begin{equation*} p(v)=k\cdot v^3 \end{equation*}
    where \(v\) is the wind speed in mph.
    1. If a wind speed of 20 mph generates 80 watts of power, write an equation for \(p(v)\text{.}\)
    2. Using your equation from ItemΒ 8.a, how much power will a wind speed of 10 mph generate?
    3. Using your equation from ItemΒ 8.a, what is the wind speed when the windmill is generating 100 watts of power?
  9. For each angle \(\theta\) below, find \(\sin \theta\text{,}\) \(\cos \theta\text{,}\) \(\tan \theta\text{,}\) \(\sec \theta\text{,}\) \(\csc \theta\) and \(\cot \theta\text{.}\)
    1. \(\displaystyle \theta=-\pi\)
    2. \(\displaystyle \theta=\frac{20\pi}{3}\)
    3. \(\displaystyle \theta=\frac{7 \pi}{2}\)