# Cosine Law

- Author:
- Whan Ki Lee, slik

- Topic:
- Cosine

A demonstration of the Cosine rule.
Drag the red points.

The proof for angle A being acute is given.
Determine the proof of the Cosine Rule when angle A is obtuse.

- Author:
- Whan Ki Lee, slik

- Topic:
- Cosine

A demonstration of the Cosine rule.
Drag the red points.

The proof for angle A being acute is given.
Determine the proof of the Cosine Rule when angle A is obtuse.