Double Angles

Use the checkboxes below to explore the difference between 2sin(x) and sin(2x).

This is a Java Applet created using GeoGebra from www.geogebra.org - it looks like you don't have Java installed, please go to www.java.com

Questions:
1. Why is 2sin(x) a triangle that has twice the width and twice the height of the original green triangle?

2. When are sin(2x) and sin(x) the same? When are sin(x) and 2sin(x) the same? Why is that?

3. How many times does sin(2x) go around the unit circle while sin(x) goes around one full time?

Dixie Christensen, 23 November 2013, Created with GeoGebra