# Difference between revisions of "Law of Cosines"

The Law of Cosines is a formula used in finding lengths and angles of a triangle. For sides a, b, and c with opposite angles A, B, and C respectively:

$c^2 = a^2 + b^2 - 2ab\cos C$

$b^2 = a^2 + c^2 - 2ac\cos B$

$a^2 = b^2 + c^2 - 2bc\cos A$