## Basics of Trigonometry

### Example:

Determine the six trigonometric ratios for angle D in the right triangle below.

$\mathrm{sin}\theta =\frac{\text{Opposite Side}}{\text{Hypotenuse}}=\frac{4}{5}$
$\mathrm{cos}\theta =\frac{\text{Adjacent Side}}{\text{Hypotenuse}}=\frac{3}{5}$
$\mathrm{tan}\theta =\frac{\text{Opposite Side}}{\text{Adjacent Side}}=\frac{4}{3}$
$\mathrm{sec}\theta =\frac{\text{Hypotenuse}}{\text{Adjacent Side}}=\frac{5}{4}$
$\text{cosec}\theta =\frac{\text{Hypotenuse}}{\text{Opposite Side}}=\frac{5}{3}$
$\mathrm{cot}\theta =\frac{\text{Adjacent Side}}{\text{Opposite Side}}=\frac{3}{4}$