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Active Prelude to Calculus

Preview Activity 2.3.1.
If we consider the unit circle with 16 labeled special points in Figure 2.3.1, start at \(t = 0\text{,}\) and traverse the circle counterclockwise, we may view the height, \(h\text{,}\) of the traversing point as a function of the angle, \(t\text{,}\) in radians. From there, we can plot the resulting \((t,h)\) ordered pairs and connect them to generate the circular function pictured in the following figure, which tracks the height of a point traversing the unit circle.
(a)
What is the exact value of \(f( \frac{\pi}{4} )\text{?}\) of \(f( \frac{\pi}{3} )\text{?}\)
(b)
Complete the following table with the exact values of \(h\) that correspond to the stated inputs.
\(t\) \(0\) \(\frac{\pi}{6}\) \(\frac{\pi}{4}\) \(\frac{\pi}{3}\) \(\frac{\pi}{2}\) \(\frac{2\pi}{3}\) \(\frac{3\pi}{4}\) \(\frac{5\pi}{6}\) \(\pi\)
\(h\)
\(t\) \(\pi\) \(\frac{7\pi}{6}\) \(\frac{5\pi}{4}\) \(\frac{4\pi}{3}\) \(\frac{3\pi}{2}\) \(\frac{5\pi}{3}\) \(\frac{7\pi}{4}\) \(\frac{11\pi}{6}\) \(2\pi\)
\(h\)
(c)
What is the exact value of \(f( \frac{11\pi}{4} )\text{?}\) of \(f( \frac{14\pi}{3} )\text{?}\)
(d)
Give four different values of \(t\) for which \(f(t) = -\frac{\sqrt{3}}{2}\text{.}\)