Frequently Asked Questions About Trigonometry

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Q: What is trigonometry?
A: Trigonometry is the study of how the sides and angles of a triangle are related to each other.

Q: WHAT? That’s all?
A: Yes, that’s all. It’s all about triangles, and you can’t get much simpler than that.

Q: You mean trigonometry isn’t some big, ugly monster that makes students turn green, scream, and die?
A: No. It’s just triangles.

Q: Oh. But isn’t that boring?
A: We’ll try to make it a little more fun by letting you play around with the triangles interactively.

Let’s start. Click on a topic to go to that page. If this is your first visit to these pages, we recommend that you start with the first item in the list.

• Stick and Shadows (part 1)
• Stick and Shadows (part 2)
• Shadows and Triangle
• Measuring the Sides
• sine and cosine
• Going in Circles
• Too Many Numbers
• sine and cosine Do "the Wave"
• Frequency and Amplitude
• Adding Waves
• A Quick Review
• Off on a Tangent
• Surveying the Uses of Trigonometry
• A Few Final Words

This material assumes that you know:

• How to measure angles.
• That a right angle is is 90 degrees.
• The sides of a triangle: the base, the height, and the hypotenuse.

If you aren’t familiar with these concepts, you’ll have to ask your math teacher to assist you with them.

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