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# Trigonometry

Big, fancy word, right? Don't be fooled. Looking at the prefix, tri-, you could probably assume that trigonometry ("trig" as it's sometimes called) has something to do with triangles. You would be right! Trig is the study of the properties of triangles. Why is it important? It's used in measuring precise distances, particularly in industries like satellite systems and sciences like astronomy. It's not only space, however. Trig is present in architecture and music, too. Now you may wonder...how is knowing the measurement and properties of triangles relevant to music?? THAT is a great question. Maybe you'll learn the answer from us in these tutorials!
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Basic trigonometry
All content in “Basic trigonometry”

### Basic trigonometric ratios

In this tutorial, you will learn all the trigonometry that you are likely to remember in ten years (assuming you are a lazy non-curious, non-lifelong learner). But even in that non-ideal world where you forgot everything else, you'll be able to do more than you might expect with the concentrated knowledge you are about to get.

### Trigonometric ratios and similarity

In this tutorial, we will build on our understanding of similarity to get a deeper appreciation for the motivation behind trigonometric ratios and relationships.

### Trig ratio application problems

You are now familiar with the basic trig ratios. We'll now use them to solve a whole bunch of real-world problems. Seriously, trig shows up a lot in the real-world.

### Reciprocal trig functions

You're now familiar with sine, cosine and tangent. Now you'll see that mathematicians have also defined functions that are the reciprocal of those: cosecant, secant and cotangent.