What does it mean to be differentiable to someone?
Being differentiable means that you have a derivative. It means that if you have a graph, that graph is going to be smooth. Further, our superjet also is not differentiable everywhere, because our superjet has this kink in the curve where there is no tangent.
Why are complex functions infinitely differentiable?
The existence of a complex derivative means that locally a function can only rotate and expand. That is, in the limit, disks are mapped to disks. This rigidity is what makes a complex differentiable function infinitely differentiable, and even more, analytic.
Can straight lines be differentiable?
Differentiation can only be applied to functions whose graphs look like straight lines in the vicinity of the point at which you want to differentiate. After all, differentiating is finding the slope of the line it looks like (the tangent line to the function we are considering) No tangent line means no derivative.
How do you know if a complex function is differentiable?
Definition – Complex-Differentiability & Derivative. The function f is complex-differentiable at an interior point z of A if the derivative of f at z, defined as the limit of the difference quotient f′(z)=limh→0f(z+h)−f(z)h f ′ ( z ) = lim h → 0 f ( z + h ) − f ( z ) h exists in C.
Does a function need to be continuous to be differentiable?
We see that if a function is differentiable at a point, then it must be continuous at that point. If is not continuous at , then is not differentiable at . Thus from the theorem above, we see that all differentiable functions on are continuous on .
Is a line differentiable?
Hence, differentiability is when the slope of the tangent line equals the limit of the function at a given point. This directly suggests that for a function to be differentiable, it must be continuous, and its derivative must be continuous as well.
What does differentiable mean in calculus?
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. As a result, the graph of a differentiable function must have a (non-vertical) tangent line at each point in its domain, be relatively smooth, and cannot contain any breaks, bends, or cusps.
What is the function of a complex variable?
In the narrow sense of the term, the theory of function of a complex variable is the theory of analytic functions (cf. Analytic function) of one or several complex variables. As an independent discipline, the theory of functions of a complex variable took shape in about the middle of the 19th century as the theory of analytic functions.
When is a function not differentiable?
At zero, the function is continuous but not differentiable. If f is differentiable at a point x 0, then f must also be continuous at x 0. In particular, any differentiable function must be continuous at every point in its domain. The converse does not hold: a continuous function need not be differentiable.
When a function is differentiable?
In general a function is differentiable on an interval if the function is smooth on that interval, meaning it has no abrupt changes in direction on the interval. If a function has a sharp change in direction at some point the derivative won’t exist at that point.
