Law of Cosines Calculator
Solve triangles using the Law of Cosines. Calculate the third side or angles.
Common Use Cases
- checking formulas and intermediate answers
- supporting homework or exam preparation
- validating manual calculations quickly
What is Law of Cosines Calculator?
The Law of Cosines relates the sides and one angle of any triangle: c² = a² + b² - 2ab cosC.
How to Use This Tool
- 1Enter known sides and the included angle (SAS)
- 2Alternatively, enter all three sides (SSS)
Example
Input
a=3, b=4, C=90°
Output
c=5
Before You Rely on This Result
UtilityNest keeps this tool simple on purpose: the goal is to make the task easy to understand, fast to complete, and straightforward to double-check.
- Review the inputs once more before you copy, save, or share the result.
- Use the example and FAQ on this page to sense-check how the tool behaves.
- When the result matters, compare one more scenario or related tool before acting on it.
Frequently Asked Questions
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