91Ó°ÊÓ

Find the amplitude and the period and sketch the graph of the equation: A. \(y=4 \sin x\) B. \(y=\sin 4 x\) C. \(y=\frac{1}{4} \sin x\) D. \(y=\sin \frac{1}{4} x\) E. \(y=2 \sin \frac{1}{4} x\) F. \(y=\frac{1}{2} \sin 4 x\) G. \(y=-4 \sin x\) H. \(y=\sin (-4 x)\)

Find the reference angle \(\theta_{R}\) if \(\theta\) has the given measure. (a) \(3 \pi / 4\) (b) \(4 \pi / 3\) \((c)-\pi / 6\) \((d) 9 \pi / 4\)

Find the amplitude, the period, and the phase shift and sketch the graph of the equation. \(y=4 \cos \left(x-\frac{\pi}{4}\right)\)

Exer. \(25-28:\) Express the angle in terms of degrees, minutes, and seconds, to the nearest second. $$63.169^{\circ}$$

A regular octagon is inscribed in a circle of radius 12.0 centimeters. Approximate the perimeter of the octagon.

A ship leaves port at 1: 00 P.M. and sails in the direction \(\mathrm{N} 34^{\circ} \mathrm{W}\) at a rate of \(24 \mathrm{mi} / \mathrm{hr}\). Another ship leaves port at 1: 30 p.M. and sails in the direction \(N 56^{\circ} \mathrm{E}\) at a rate of \(18 \mathrm{mi} / \mathrm{hr}\) (a) Approximately how far apart are the ships at 3: 00 P.M.? (b) What is the bearing, to the nearest degree, from the first ship to the second?