## FANDOM

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The trigonometric ratios are ratios of sides to one particular angle. These especially apply to right triangles and circles.

## BasicEdit

Here are the three basic trigonometric ratios you learn in geometry, using the Greek letter theta to represent an angle other than the right angle.

### SineEdit

$\sin{\theta\,}\, = \frac{opposite}{hypotenuse}\,$

### CosineEdit

$\cos{\theta\,}\, = \frac{adjacent}{hypotenuse}\,$

### TangentEdit

$\tan{\theta\,}\, = \frac{opposite}{adjacent}\,$

Here are three advanced trigonometric ratios you will learn by the time you get to calculus, again using theta.

### CosecantEdit

$\csc{\theta\,}\, = \frac{hypotenuse}{opposite}\,$

### SecantEdit

$\sec{\theta\,}\, = \frac{hypotenuse}{adjacent}\,$

### CotangentEdit

$\cot{\theta\,}\, = \frac{adjacent}{opposite}\,$

### DegreesEdit

You use degrees when finding lengths and measurements of legs and angles in triangles.

$\sin{13}\, \approx\, 0.224951054343865...$
$\sin^{-1}{\frac{5}{6}\,}\, \approx\, 56.44269023807929...$

As is true for both triangles and circles, inverse trigonometric ratios will always give you the measure of the angle in question.

$\sin{13}\, \approx\, 0.420167036826641...$
$\sin^{-1}{\frac{5}{6}\,}\, \approx\, 0.985110783337746...$