Ximpledu

Law of Cosines

See how to use the law of cosines to solve a triangle.
2 examples and their solutions.

Law of Cosines

Formula


a2 = b2 + c2 - 2bccos A
Use the law of sines when:
2 sides, 1 angle → 1 side
3 sides → 1 angle.

Example

Solution

Example

Solution