91Ó°ÊÓ

Applying Trigonometric ldentities, use the given function value(s) and the trigonometric identities to find the indicated trigonometric functions. $$\sec \theta=5$$ $$\begin{array}{ll}{\text { (a) } \cos \theta} & {\text { (b) } \cot \theta} \\\ {\text { (c) } \cot \left(90^{\circ}-\theta\right)} & {\text { (d) } \sin \theta}\end{array}$$

Geometry Find the length of the sides of a regular pentagon inscribed in a circle of radius 25 inches.

Applying Trigonometric ldentities, use the given function value(s) and the trigonometric identities to find the indicated trigonometric functions. $$\cot \alpha=5$$ $$\begin{array}{ll}{\text { (a) } \tan \alpha} & {\text { (b) } \csc \alpha} \\\ {\text { (c) }} & {\cot \left(90^{\circ}-\alpha\right)} & {\text { (d) } \cos \alpha}\end{array}$$

Finding a Reference Angle.Find the reference angle \(\theta^{\prime}\) and sketch \(\theta\) and \(\theta^{\prime}\) in standard position. $$\theta=160^{\circ}$$

Graphing a Trigonometric Function In Exercises \(39-48\) , use a graphing utility to graph the function. (Include two full periods.) $$y=-\csc (4 x-\pi)$$

Use an inverse trigonometric function to write \(\theta\) as a function of \(x .\)

Using a Calculator In Exercises \(43-48,\) use a calculator to evaluate the trigonometric function. Round your answer to four decimal places. (Be sure the calculator is in the correct mode.) $$\csc 0.8$$

Convert the angle measure from radians to degrees. Round to three decimal places. \(-4.2 \pi\)

Sketching the Graph of a sine or cosine Function, sketch the graph of the function. (Include two full periods.) $$ y=\cos 2 \pi x $$

Graphing a Trigonometric Function In Exercises \(39-48\) , use a graphing utility to graph the function. (Include two full periods.) $$y=2 \sec (2 x-\pi)$$