- When can a derivative not exist?
- Can a function be continuous with a hole?
- What is the limit?
- What happens when derivative is zero?
- Can a function with a hole be differentiable?
- Is there a limit if theres a hole?
- Can limits exist at corners?
- How do you prove differentiability?
- Can a hole be undefined?
- Does the second derivative always exist?
- How do you know if a function is not differentiable?

## When can a derivative not exist?

If there derivative can’t be found, or if it’s undefined, then the function isn’t differentiable there.

So, for example, if the function has an infinitely steep slope at a particular point, and therefore a vertical tangent line there, then the derivative at that point is undefined..

## Can a function be continuous with a hole?

The function is not continuous at this point. This kind of discontinuity is called a removable discontinuity. Removable discontinuities are those where there is a hole in the graph as there is in this case. … In other words, a function is continuous if its graph has no holes or breaks in it.

## What is the limit?

In mathematics, a limit is the value that a function (or sequence) “approaches” as the input (or index) “approaches” some value. Limits are essential to calculus and mathematical analysis, and are used to define continuity, derivatives, and integrals.

## What happens when derivative is zero?

When x is a critical point of f(x) and the second derivative of f(x) is zero, then we learn no new information about the point. The point x may be a local maximum or a local minimum, and the function may also be increasing or decreasing at that point.

## Can a function with a hole be differentiable?

A function with a removable discontinuity at the point is not differentiable at since it’s not continuous at . Continuity is a necessary condition. … Thus, is not differentiable. However, you can take an arbitrary differentiable function .

## Is there a limit if theres a hole?

The limit at a hole: The limit at a hole is the height of the hole. is undefined, the result would be a hole in the function. Function holes often come about from the impossibility of dividing zero by zero.

## Can limits exist at corners?

The limit is what value the function approaches when x (independent variable) approaches a point. takes only positive values and approaches 0 (approaches from the right), we see that f(x) also approaches 0. itself is zero! … exist at corner points.

## How do you prove differentiability?

1 Answer. To show that f is differentiable at all x∈R, we must show that f′(x) exists at all x∈R. Recall that f is differentiable at x if limh→0f(x+h)−f(x)h exists.

## Can a hole be undefined?

Holes and Rational Functions A hole on a graph looks like a hollow circle. … As you can see, f ( − 1 2 ) is undefined because it makes the denominator of the rational part of the function zero which makes the whole function undefined.

## Does the second derivative always exist?

But if the second derivative doesn’t exist, then no such reasoning is possible, i.e. for such points you don’t know anything about the possible behaviour of the first derivative. but the function does not have an inflection point. The function y=x1/3 has as its second derivative y″=−29x−5/3, which is undefined at x=0.

## How do you know if a function is not differentiable?

We can say that f is not differentiable for any value of x where a tangent cannot ‘exist’ or the tangent exists but is vertical (vertical line has undefined slope, hence undefined derivative).