Transcript 5.1.5 cosine function notes

5.1.5 The Cosine Function
Essential Question:
How do you graph a cosine function using the unit circle and radians?
Main Idea
• We are going continue exploring periodic functions.
Today we will study a specific periodic function: the
cosine function.
– Cosine is the x-value on the unit circle, so we will graph
what happens to it as we go around the unit circle.
– We can use degrees or radians; radians is the measure of
choice for mathematicians when it comes to trigonometry.
– Like other families of functions, it has a parent function.
– Like other periodic functions, it has a cycle, period, and
amplitude.
The Cosine Function
• Cosine Function: the function represented by
the angle measure in standard position on a
unit circle.
Comparing Sine & Cosine
The Cosine Function
Sketching a Cosine Function
Practice
Writing a Cosine Function
Solving a Cosine Equation
Finding Solutions
Summary
• Answer the essential questions in detailed,
complete sentences to make a paragraph.
• How do you graph a cosine function using the
unit circle and radians?
• Create 3-5 study questions in the left column to
correspond to the notes.