In the case of an implicit function, where , is treated as a function of , and each term is differentiated with respect to to find .
For the equation of a circle, , is not explicitly a function of . However: When , When ,
In each case, becomes a function of defined over the closed interval . Generally, for an equation , by restricting the domain of and , can become a function of . In this context, the equation is referred to as an implicit function of in terms of .
Additionally, the points satisfying the equation represent a curve on the coordinate plane.
Consider the equation . By treating as a function of and differentiating each term with respect to :
Thus, as long as
Differentiation of Inverse Functions
If a differentiable function has an inverse , and if the inverse is differentiable, then: