Differentiable Function - Wikipedia - en.wikipedia.org  ## Metadata - Author: **en.wikipedia.org** - Full Title: Differentiable Function - Wikipedia - Category: #articles - Tags: #mathematic - URL: https://en.wikipedia.org/wiki/Differentiable_function#:~:text=In%20mathematics%2C%20a,or%20cusp. ## Highlights - In mathematics, a differentiable function of one real variable is a function whose derivative exists at each point in its domain. In other words, the graph of a differentiable function has a non-vertical tangent line at each interior point in its domain. A differentiable function is smooth (the function is locally well approximated as a linear function at each interior point) and does not contain any break, angle, or cusp.