1.5 Trigonometric Functions



The trigonometric functions are important for modeling periodic behavior. The circular function definitions of sine and cosine are introduced, as are the definitions of the tangent, the secant, the cosecant, and the cotangent functions. The trigonometric identities that follow readily from symmetry considerations are also developed.

By the end of your studying, you should know:

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Evaluate the following exactly:

A particle moving back and forth on the x axis has its position given as a function of time t as follows:

Where is the particle when t = 0 and how long does it take to return to this position?

Find all solutions to the following equation:


Definitions of sin(x) and cos(x)
Trigonometric Identities


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Interesting Application

Do you see trig at work?

1.4 Defining New Functions from Old Table of Contents 1.6 Exponential and Logarithm Functions

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Copyright © 2005 Donald L. Kreider, C. Dwight Lahr, Susan J. Diesel