The Law of Cosines - Math is Fun
The Law of Cosines says: c 2 = a 2 + b 2 − 2ab cos (C) Put in the values we know: c 2 = 8 2 + 11 2 − 2 × 8 × 11 × cos (37º) Do some calculations: c 2 = 64 + 121 − 176 × 0.798…
Law of cosines - Wikipedia
In trigonometry, the law of cosines (also known as the cosine formula or cosine rule) relates the lengths of the sides of a triangle to the cosine of one of its angles.
Law of Cosines Calculator
Aug 1, 2025 · Uses the law of cosines to calculate unknown angles or sides of a triangle. In order to calculate the unknown values you must enter 3 known values. To calculate any angle, A, B …
Law of Cosines - Formula, Proof, and Examples
The Law of Cosines, also called Cosine Rule or Cosine Law, states that the square of a side of a triangle is equal to the sum of the squares of the other two sides minus twice their product …
Cosine Rule - GCSE Maths - Steps, Examples & Worksheet
The cosine rule (or the law of cosines) is a formula which can be used to calculate the missing sides of a triangle or to find a missing angle. To do this, we need to know the two …
Law of Cosines: How and when to use Formula, examples ...
Law of cosines formula to find the side or the angle in a triangle. Model and practice problems worked out step by step with pictures.
Cosine Rule - GeeksforGeeks
Jul 23, 2025 · In this article, we will discuss the introduction, definition, properties, formula of the Cosine Rule, and its meaning. We will also understand the proof of the Cosine Rule.