Table of Contents
Just an easy way to remember how Sine, Cosine and Tangent work:
Soh… (Sine = Opposite / Hypotenuse)
…cah… (Cosine = Adjacent / Hypotenuse)
…toa (Tangent = Opposite / Adjacent)
Firstly, the names Opposite, Adjacent and Hypotenuse come from the right triangle:
- “Opposite” is opposite to the angle θ
- “Adjacent” is adjacent (next to) to the angle θ
- “Hypotenuse” is the longest one
Sine, Cosine, & Tangent
Sine, Cosine, and Tangent are the 3 main functions in trigonometry.
They are often shortened to sin, cos and tan.
The calculation is simply one side of a right angled triangle divided by another side. we just have to know which sides, and that is where “sohcahtoa” helps.
For a triangle with an angle θ , the functions are calculated this way:
|Sine||soh…||sin(θ) = opposite / hypotenuse|
|Cosine||…cah…||cos(θ) = adjacent / hypotenuse|
|Tangent||…toa||tan(θ) = opposite / adjacent|