Beginner’s Trigonometry

In 6 Lessons

By Rebecca Adcock

You thought you were doing a good job surviving Algebra and Geometry and now you’re signed up to study “Trigonometry”. So what is it? You probably noticed in Geometry class that you spent more time studying triangles and circles than any other figure. And probably more time on triangles than on circles. Trigonometry is a branch of mathematics, related to geometry, that studies the relationships between the sides of triangles and their angles. Three of these relationships are the sine, cosine and tangent functions. Before we can study these relationships, we need to review the Pythagorean Theorem and briefly study special right triangles. That’s what Lessons 1 and 2 are all about. Then the fun stuff starts in Lesson 3. I’m serious! Trig is really neat. Find out for yourself…

In case you were wondering (and I’m sure you were) the word trigonometry comes from the Greek words trigonon meaning triangle and metron meaning measure. It was originally used to answer questions in geography and astronomy.

Work through each lesson at your own pace. After completing a lesson , go to Lesson Assessments and test yourself. Answers are found in Teacher’s Resource. But don’t look until you’ve worked through the assessments!

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Lesson #6: Sine and Cosine Graphs

Lesson Assessments

Teacher’s Resource

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