Law of sines

In trigonometry, the law of sines is a mathematical equation relating the lengths of the sides of any triangle to the sines of its angles. According to the law, where a, b, and c are the lengths of the sides of a triangle, and α, β, and γ are the opposite angles, while R is the radius of the triangle's circumcircle. When the last part of the equation is not used, the law is sometimes stated using the reciprocals; The law of sines can be used to compute the remaining sides of a triangle when two angles and a side are known—a technique known as triangulation.

It can also be used when two sides and one of the non-enclosed angles are known.
In some such cases, the triangle is not uniquely determined by this data and the technique gives two possible values for the enclosed angle.

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