Kelly's story is truly inspirational. Kelly has shown that pure determination, dedication and hard work can and does change a person's life. At Life Leisure we have loved being part of Kelly's journey.
In calculus (a branch of mathematics), a differentiable function of one real variable is a function whose derivative exists at each point in its domain.
differentiation. n. 1. the act, process, or result of differentiating. 2. (Mathematics) maths an operation used in calculus in which the derivative of a function or variable is determined; the inverse of integration. See integration 6.