Function bounded on [a,b] with finite discontinuities is Riemann integrable

In summary, to prove that a function bounded on [a,b] with finite discontinuities is Riemann integrable on [a,b], the following equation can be used: if f is R-integrable on [a,b], then \forall \epsilon > 0 \exists a partition P of [a,b] such that U(P,f)-L(P,f)<\epsilon. This means that the term on the LHS must be made <ε by choosing c_j'' and c_j' to be as close as desired and small enough to neglect the second term on the RHS.
  • #1
natasha d
19
0

Homework Statement



to prove that a function bounded on [a,b] with finite discontinuities is Riemann integrable on [a,b]

Homework Equations



if f is R-integrable on [a,b], then [itex]\forall[/itex] [itex]\epsilon[/itex] > 0 [itex]\exists[/itex] a partition P of [a,b] such that U(P,f)-L(P,f)<[itex]\epsilon[/itex]


The Attempt at a Solution


the term on the LHS must be made <ε
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  • #2
You're almost there! You can choose your c_j'' and c_j' to be as close as you want, can't you?
 
  • #3
make it small enough to neglect the second term on the RHS?
 
  • #4
Thats the idea. You can choose c_j''-c_j' to be less than some multiple of epsilon and then proceed.
 
  • #5
got it thanks
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FAQ: Function bounded on [a,b] with finite discontinuities is Riemann integrable

What does it mean for a function to be bounded on [a,b]?

A function is considered bounded on [a,b] if there exists a number M such that for all x in [a,b], the absolute value of the function is less than or equal to M. In other words, the function does not have any extreme values that go to infinity.

What are finite discontinuities?

Finite discontinuities refer to points on the function where the function is not continuous, but the discontinuity is not infinite. This means that the function has a jump or a point where it is undefined, but the value at that point is not approaching infinity or negative infinity.

What is Riemann integration?

Riemann integration is a method of calculating the definite integral of a function. It involves breaking up the interval [a,b] into smaller subintervals, approximating the function on each subinterval with a rectangle, and then summing the areas of the rectangles to find the total area under the curve.

How can a function with finite discontinuities be Riemann integrable?

A function with finite discontinuities can be Riemann integrable if the discontinuities do not have a significant impact on the overall area under the curve. This means that the sum of the areas of the rectangles used to approximate the function on each subinterval must approach the true area under the curve as the subintervals become smaller and smaller.

What are some real-world applications of this concept?

One example of a real-world application of this concept is in physics, where the Riemann integral is used to calculate the work done by a varying force on an object. Another example is in economics, where the Riemann integral is used to calculate the total cost or revenue for a business with changing prices over time.

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