# Important information about application of trigonometric functions in real life

As a group, work together to submit the answers to the following problems. Use the Small Group Discussion Board to divide tasks, discuss strategies for solving problems, and check each other's work. The finished product should be one combined document for the entire group, showing all calculations and graphical representations used.

1. Find the length L from point A to the top of the pole.

2. Lookout station A is 15 km west of station B. The bearing from A to a fire directly south of B is S 37°50' E. How far is the fire from B?

3. The wheels of a car have a 24-in. diameter. When the car is being driven so that the wheels make 10 revolutions per second, how far with the car travel in one minute?

4. A regular octagon is inscribed in a circle of radius 15.8 cm. Find the perimeter of the octagon.

5. What is the angle of elevation of the sun when a 35-ft mast casts a 20-ft shadow?

6. A V-gauge is used to find the diameters of pipes. In the figure on p. 373 in the text, the measure of angle AVB is 54°. A pipe is placed in the V-shaped slot and the distance VP is used to predict the diameter.

a. Suppose that the diameter of a pipe is 2 cm. What is the distance VP?

b. Suppose that the distance VP is 3.93 cm. What is the diameter of the pipe?

c. Find the formula for d in terms of VP.

d. Find a formula for VP in terms of d.

The line VP is calibrated by listing the corresponding diameters as its units. This, in effect, establishes a function between VP and d.

Please add your file.

Reference:

Bittinger, M. L., & Beecher, J. A. (2000). Trigonometry update. Reading, MA: Addison Wesley.

1. Consider the graph of y = tan x.

(a) How does it show that the tangent of 90 degrees is undefined?

(b) What are other undefined x values?

(c) What is the value of the tangent of angles that are close to 90 degrees (say 89.9 degrees and 90.01 degrees)?

(d) How does the graph show this?

2. A nautical mile depends on latitude. It is defined as length of a minute of arc of the earth's radius. The formula is N(P) = 6066 - 31 cos 2P, where P is the latitude in degrees.

(a) Using the Cybrary and other course resources, find the exact latitude (to 4 decimal places) of where you live, used to live, work, or used to work (include the zip code).

(b) Using the latitude found in part a and the formula N(P), find the length of a nautical mile to the nearest foot at that location.

(c) Next, use the formula N(P) to find the latitude where the nautical mile is 6051 feet.

(d) Name two cities in the Northern Hemisphere and two in the Southern that are close to the latitude found in part c.

3. When graphed using polar coordinates, the center of a regular nonagon is at the origin and one vertex is at (6, 0 degrees) or (6, 0 radians). Find the polar coordinates of the other vertices in both degrees and radians.

#### Solution Preview

Plsease see the detailed and step-by step solutions in the attached WORD file.

1. For the pole, the angle between BC and AC is 90 ...

#### Solution Summary

The solution is comprised of detailed explanations of the application of the trigonometric functions such as sine, cosine, and tangent. With diagrams and step-by-step contents, the solution should provide the students a clear understanding of trigonometric functions in real life.