When Charlie explains how to crack a counterfeiting ring, he talks about the intricate engraving used in banknotes, called guilloche. He explains that this is "created by the addition and multiplication of nested sine waves."
Students will see what it means to combine trigonometric functions using addition and multiplication.
Before the Activity
Download the attached PDF and look over the Teacher Page.
During the Activity
Discuss the materials from the Student Page with your class.
After the Activity
Encourage students to explore web sites and questions from the Extensions Page.