12.7 Graphing Trigonometric Functions Day 1: Sine and Cosine
Graph the following in your calculator. Find the period and minimum and maximum values for each function. 1. f(θ) = sin θ 2. f(θ) = cos θ
The amplitude of the graph of sine and cosine functions equals half The difference between the maximum and the minimum values.
Finding Amplitude and Period Example 1a
Example 1b
Example 2
Example 3
Applications
Example 4 Humans can hear sounds with a frequency of 40 Hz. Find the period of the function that models the sound waves. Let the amplitude equal 1 unit. Write a sine equation to represent the sound wave y as a function of time t.
Example 5 The bass tuba can produce sounds with as low a frequency as 50 Hz. Find the period of the function that models the sound waves. Let the amplitude equal 2 unit. Determine the correct cosine equation to represent the sound wave y as a function of time t.