# Is every integrable function is continuous?

## Is every integrable function is continuous?

Continuity implies integrability; if some function f(x) is continuous on some interval [a,b], then the definite integral from a to b exists. While all continuous functions are integrable, not all integrable functions are continuous.

Can you integrate non continuous functions?

We evaluate integrals with discontinuous integrands by taking a limit; the function is continuous as x approaches the discontinuity, so FTC II will work. When the discontinuity is at an endpoint of the interval of integration [a,b], we take the limit as t approaces a or b from inside [a,b].

### Can a non continuous function be Riemann integrable?

Discontinuous functions can be integrable, although not all are. Specifically, for Riemann integration (our normal basic notion of integrals) a function must be bounded and defined everywhere on the range of integration and the set of discontinuities on that range must have Lebesgue measure zero.

Can you take the Antiderivative of a non continuous function?

No. The best you can do is a function g that is continuous everywhere, and differentiable with g′(x)=f(x) for all x except at x=0. Since g′(x) has different one sided limits at x=0, g cannot be differentiable there.

## Is every continuous function Riemann integrable?

Theorem. All real-valued continuous functions on the closed and bounded interval [a, b] are Riemann- integrable.

Is every differentiable function integrable?

Well, If you are thinking Riemann integrable, Then every differentiable function is continuous and then integrable! However any bounded function with discontinuity in a single point is integrable but of course it is not differentiable!

### Are there functions that don’t have integrals?

Definitely not. Simple examples include things like e-x2 and xx. Of course, these functions do have integrals – they’re smooth and continuous and all that, so they have areas under their curves – so (using the fundamental theorem of calculus) you can use those areas to construct, at each point, its antiderivative.

Which is an example of a non-continuous, integrable function?

You can use these theorems to give examples of noncontinuous integrable functions. By 1 and 3, any function that’s continuous except at finitely many places is integrable. For example, the signum function is not continuous at 0… Loading…

## How is integrability related to the property of continuous?

It’s enough to change the value of a continuous function at just one point and it is no longer continuous. Integrability on the other hand is a very robust property. If you make finitely many changes to a function that was integrable, then the new function is still integrable and has the same integral.

Can a definite integral be a non integrable function?

The integral can be defined as an improper Riemann integral and happens to equal π. This is just a warning that ‘not integrable’ (in the Lebesgue sense) doesn’t mean that the definite integral doesn’t have a value. ( x) / x and thus computing the integral over an interval using the fundamental theorem of calculus.

### Can a continuous function be a Riemann integrable?

every continuous function is Riemann integrable,continuity is certainly not necessary. I dont know anything about measure. Define f to be identically 0 on R, except that f ( 0) = 1. To see that this is Riemann integrable, note that the lower sums are all 0 (suppose we’re integrating on [ − 1, 1], for clarity).