Implicitly defined function

Revision as of 19:32, 8 September 2009 by JBL (talk | contribs) (moved Implicit function to Implicitly defined function: makes more sense ... am open to other suggestions)

An implicit function is a function that isn't explicit. That is, it doesn't express $y$ in terms of $x$. It is often difficult or impossible to rewrite an implicit function in explicit form.

Examples

$x^2(x^2 + y^2) = y^2$

$x^2 + y^2 = (1 + tan^{-1}\frac{y}{x})^2$

$x^2 + y^2 = x^2 y^2$