Formula

In mathematics, a formula is a fact, rule, or principle that is expressed in terms of mathematical symbols. Examples of formulas include equations, equalities, identities, inequalities, and asymptotic expressions.

The term "formula" is also commonly used in the theory of logic to mean sentential formula (also called a propositional formula), i.e., a formula in propositional calculus.

The correct Latin plural form of formula is "formulae," although the less pretentious-sounding "formulas" is more commonly used.

REFERENCES

Carr, G. S. Formulas and Theorems in Pure Mathematics. New York: Chelsea, 1970.

Spiegel, M. R. Mathematical Handbook of Formulas and Tables. New York: McGraw-Hill, 1968.

Tallarida, R. J. Pocket Book of Integrals and Mathematical Formulas, 3rd ed. Boca Raton, FL: CRC Press, 1992.

Weisstein, E. W. "Books about Handbooks of Mathematics." http://www.ericweisstein.com/encyclopedias/books/HandbooksofMathematics.html.html.