FUNCTION

FUNCTION, a term used in analytics for an algebraical expression any how compounded of a certain letter or quantity with other quantities or numbers; and the expression is said to be a function of that letter or quantity. Thus $a\; =\; 4x$, or $a\; =\; x\; +\; 3x^2$, or $2x\; =\; a\backslash sqrt\{a^2\; -\; x^2\}$, or $x$, or $x^2$, is each of them a function of the quantity $x$.