MathLiveCosine as a ratio in a right triangle
The cosine of an acute angle in a right triangle is the length of the side adjacent to the angle divided by the length of the hypotenuse. It is the basic definition used in trigonometry to relate angles to side lengths.
\cos\,\theta = \frac{\text{adjacent}}{\text{hypotenuse}}What the symbols mean
| an acute angle in a right triangle | |
| length of the side next to the angle θ, not the hypotenuse | |
| length of the side opposite the right angle |
About this formula
- FieldMathematics
- TopicTrigonometry
- LevelHigh school
- Also calledcosine definition, cos theta, cosine right triangle, cosine ratio, adjacent over hypotenuse, SOH CAH TOA cosine
- SourceWikidata Q1256164
Write it in Obsidian
MathLive is a free visual math editor for Obsidian. Run Find a formula, type “cosine as a ratio in a right triangle”, and it goes into your note as editable LaTeX. You can also scan formulas from screenshots, PDFs and handwriting.