# Trigonometry » What is SOH, CAH, TOA?

Sine, cosine and tangent are called trigonometric ratios.

With the following mnemonic it is easy to remember what the formulas are for sine, cosine and tangent.

## SOH, CAH, TOA

Here SOH, CAH and TOA mean:

SOH : **s**`in`

(`A`) = **o**pposite shorter side of `A`**h**ypotenuse

CAH : **c**`os`

(`A`) = **a**djacent shorter side of `A`**h**ypotenuse

TOA : **t**`an`

(`A`) = **o**pposite shorter side of `A`**a**djacent shorter side of `A`