https://**en.wikipedia.org**/wiki/**Law_of_cosines**

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.

**www.mathsisfun.com**/algebra/trig-cosine-law.html

**The Law of Cosines**. **The Law of Cosines** (also called the Cosine Rule) is very useful for solving triangles: It works for any triangle:

**www.mathwarehouse.com**/trigonometry/**law-of-cosines**-formula-examples.php

**Law of cosines** formula to find the side or the angle in a triangle. Video tutorial, Model and practice problems plus a free worksheet with answer key!.

mathworld.wolfram.com/**LawofCosines**.html

This law can be derived in a number of ways. The definition of the dot product incorporates **the law of cosines**, so that the length of the vector from to is given by

**www.themathpage.com**/aTrig/**law-of-cosines**.htm

To find the third side of a triangle when we know two sides and their included angle. Proof of **the law of cosines**.

https://**www.khanacademy.org**/.../**law-of-cosines**/v/**law-of-cosines**#!

Sal gives a simple proof of **the Law of cosines**. ... In the last video, we had a word problem where we had-- we; essentially had to figure out the sides of a triangle, but

regentsprep.org/Regents/math/algtrig/ATT12/**lawofcosines**.htm

We can write **the Law of Cosines** for each angle around the triangle. Notice in each statement how the pattern of the letters remains the same.

https://**en.wikipedia.org**/wiki/**Law_of_sines**

In trigonometry, the **law of sines**, sine law, sine formula, or sine rule is an equation relating the lengths of the sides of any shaped triangle to the sines of its ...

hyperphysics.phy-astr.gsu.edu/hbase/lcos.html

**Law of Cosines The law of cosines** for calculating one side of a triangle when the angle opposite and the other two sides are known. Can be used in conjunction with ...

**illuminations.nctm.org**/Lesson.aspx?id=2441

In this lesson, students use right triangle trigonometry and the Pythagorean theorem to develop **the law of cosines**.