law of cosines
mathematics
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External Websites
- Story of Mathematics - The Cosine Rule – Explanation & Examples
- Open Library Publishing Platform - Pre-Calculus - Non-right Triangles: Law of Cosines
- Math is Fun Advanced - The Law of Cosines
- Mathematics LibreTexts - The Law of Cosines
- University of Utah - Department of Mathematics - Law of Cosines
- LOUIS Pressbooks - Trigonometry - The Law of Cosines
- Clark University - Law of Cosines
Also known as: cosines, law of
law of cosines, Generalization of the Pythagorean theorem relating the lengths of the sides of any triangle. If a, b, and c are the lengths of the sides and C is the angle opposite side c, then c2 = a2 + b2 − 2ab cos C.