Let a Triangle have sides of lengths , , and and let the Angles opposite these sides by
, , and . The law of tangents states

An analogous result for oblique Spherical Triangles states that

**References**

Abramowitz, M. and Stegun, C. A. (Eds.).
*Handbook of Mathematical Functions with Formulas, Graphs, and Mathematical Tables, 9th printing.*
New York: Dover, p. 79, 1972.

Beyer, W. H. *CRC Standard Mathematical Tables, 28th ed.* Boca Raton, FL: CRC Press, pp. 145 and 149, 1987.

© 1996-9

1999-05-26