Riemann Stieltjes Integral help

In summary, the Riemann Stieltjes integral is a type of integral that extends the concept of the Riemann integral to functions that are not necessarily continuous. It is used to find the area under a curve defined by a function and a second function, known as the integrator function. The main difference between the Riemann and Riemann Stieltjes integral is that in the Riemann integral, the function is integrated with respect to the variable of integration, while in the Riemann Stieltjes integral, the function is integrated with respect to another function. To calculate the Riemann Stieltjes integral, the interval of integration is divided into subintervals, and the function is evaluated
  • #1
prudens2010
1
0
Code:
Let f = 

x, for 0<=x<=1
1, for 1<x

alpha =

x^2, for 0<=x<=1
1, for 1<x

Find Integral (f) d(alpha) -- from 0 to 23

pls help!
 
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  • #2
prudens2010 said:
Code:
Let f = 

x, for 0<=x<=1
1, for 1<x

alpha =

x^2, for 0<=x<=1
1, for 1<x

Find Integral (f) d(alpha) -- from 0 to 23

pls help!

Use the definition of the R-S integral. The answer should pop right out unless I'm missing something. Where does the problem lose you?
 
  • #3
This case easily translates into an ordinary Riemann integral.
dα = 2xdx, 0≤x≤1
dα = 0, x>1
 

What is the Riemann Stieltjes integral?

The Riemann Stieltjes integral is a type of integral that extends the concept of the Riemann integral to functions that are not necessarily continuous. It is used to find the area under a curve that is defined by a function and a second function, known as the integrator function.

What is the difference between the Riemann and Riemann Stieltjes integral?

The main difference between the Riemann and Riemann Stieltjes integral is that in the Riemann integral, the function is integrated with respect to the variable of integration, while in the Riemann Stieltjes integral, the function is integrated with respect to another function, known as the integrator function.

How do you calculate the Riemann Stieltjes integral?

To calculate the Riemann Stieltjes integral, you first divide the interval of integration into subintervals. Then, you evaluate the function at each point of the subintervals and multiply it by the difference between the values of the integrator function at the endpoints of the subinterval. Finally, you add all these values together and take the limit as the width of the subintervals approaches zero.

What are the applications of the Riemann Stieltjes integral?

The Riemann Stieltjes integral has many applications in physics, engineering, economics, and other fields where the concept of accumulation is important. It is also used in probability theory, where it is used to calculate expectations of random variables.

What are the limitations of the Riemann Stieltjes integral?

The Riemann Stieltjes integral has some limitations, such as the integrator function must be monotonic and have a finite number of discontinuities. It also cannot be used to integrate functions that are not bounded or have infinite discontinuities. In these cases, other types of integrals, such as the Lebesgue integral, may be used instead.

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