91Ó°ÊÓ

Find the exact value of the trigonometric function at the given real number. $$ \begin{array}{llll}{\text { (a) } \cos \frac{5 \pi}{3}} & {\text { (b) } \cos \left(-\frac{5 \pi}{3}\right)} & {\text { (c) } \cos \frac{7 \pi}{3}}\end{array} $$

Graph the function. $$ f(x)=-1+\cos x $$

Find the exact value of the trigonometric function at the given real number. $$ \begin{array}{llll}{\text { (a) } \cos \frac{3 \pi}{4}} & {\text { (b) } \cos \frac{5 \pi}{4}} & {\text { (c) } \cos \frac{7 \pi}{4}}\end{array} $$

The given function models the displacement of an object moving in simple harmonic motion. (a) Find the amplitude, period, and frequency of the motion. (b) Sketch a graph of the displacement of the object over one complete period. $$y=5 \cos \left(\frac{2}{3} t+\frac{3}{4}\right)$$

Find the exact value of the trigonometric function at the given real number. $$ \begin{array}{llll}{\text { (a) } \sin \frac{3 \pi}{4}} & {\text { (b) } \sin \frac{5 \pi}{4}} & {\text { (c) } \sin \frac{7 \pi}{4}}\end{array} $$

7–52 Find the period and graph the function. $$y=-4 \tan x$$

\(7-12\) . Find the missing coordinate of \(P\) , using the fact that \(P\) lies on the unit circle in the given quadrant. \(P\left(\quad,-\frac{7}{25}\right) \quad \mathrm{IV}\)

The given function models the displacement of an object moving in simple harmonic motion. (a) Find the amplitude, period, and frequency of the motion. (b) Sketch a graph of the displacement of the object over one complete period. $$y=1.6 \sin (t-1.8)$$

Graph the function. $$ g(x)=2 \sin x $$

\(7-12\) . Find the missing coordinate of \(P\) , using the fact that \(P\) lies on the unit circle in the given quadrant. \(P\left(\begin{array}{cc}{P( } & {, \frac{1}{3} )} & {\text { II }}\end{array}\right.\)