Need help with numerical integration

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SUMMARY

This discussion focuses on solving the improper integral from 10 to infinity of the function (sin(1/x)/(1+x^3)) using Simpson's rule with an error precision of e=0.5*10^-4. The user is guided through the process of dividing the interval into smaller subintervals and calculating function values at these points. The Simpson's rule formula is provided, emphasizing the need for an even number of subintervals and the importance of selecting an appropriate value of n to ensure the error term meets the specified precision.

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  • Understanding of numerical integration techniques, specifically Simpson's rule.
  • Familiarity with improper integrals and error analysis.
  • Basic knowledge of calculus, including limits and function evaluation.
  • Experience with programming or using calculators for numerical computations.
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  • Learn about error analysis in numerical integration methods.
  • Study the implementation of Simpson's rule in programming languages like Python or MATLAB.
  • Explore other numerical integration techniques, such as Trapezoidal rule and Romberg integration.
  • Investigate convergence criteria for numerical methods to ensure accuracy in approximations.
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Mathematicians, engineering students, and professionals involved in numerical analysis or computational mathematics who need to approximate integrals that cannot be solved analytically.

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Im supposed to solve
integral 10 to +infinity ((sin(1/x)/(1+x^3))dx with error precision of e=0.5*10^-4. Can someone please give me detailed explenation of solving this. (Supposedly by Simpson but i get lost in the way.

P.S. sorry for bad spelling and lack of proper formula notions.
 
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I process from integral i get
1/3[ln((x+1)/sqrt(x^2-x+1))+sqrt(3)*arctg(2*sqrt(3)*x/3-sqrt(3)/3)] from M to +infinity <=1/4*10^-2

than i get

-ln((M+1)/(sqrt(M^2-M+1))) +sqrt(3)*(pi/2-arctg(2*sqrt(3)*M/3-sqrt(3)/3))<=7.5*10^-3

and i can't find any exact solution to solve that
 


Numerical integration is a method used to approximate the value of an integral when it cannot be solved analytically. In this case, we are trying to solve the integral from 10 to positive infinity of (sin(1/x)/(1+x^3))dx with an error precision of e=0.5*10^-4. This means that we want our approximation to be within 0.5*10^-4 of the actual value of the integral.

To solve this using Simpson's rule, we need to first divide the interval of integration (10 to infinity) into smaller subintervals. Simpson's rule works by approximating the curve of the function with a series of parabolas, so we need to have an even number of subintervals. Let's say we divide the interval into n subintervals, each with a width of h.

Next, we need to calculate the values of the function at the endpoints of each subinterval. In this case, our function is (sin(1/x)/(1+x^3)), so we need to calculate f(10), f(10+h), f(10+2h), and so on until we reach the endpoint of the last subinterval. We can use a calculator or a computer program to do this.

Once we have all the function values, we can use Simpson's rule formula to approximate the value of the integral. The formula is:

I ≈ (h/3) * [f(x0) + 4f(x1) + 2f(x2) + 4f(x3) + 2f(x4) + ... + 4f(xn-1) + f(xn)]

where x0 is the starting point of the interval (10 in this case), xn is the endpoint of the interval (infinity in this case), and h is the width of each subinterval (h = (infinity - 10)/n).

To meet our error precision of e=0.5*10^-4, we need to choose a value of n that will make the error term (h^4/180)*f^(4)(ξ) (where ξ is some value between 10 and infinity) less than or equal to 0.5*10^-4. This will require some trial and error, but we can start by choosing a value of n and calculating the error term. If it is larger than 0.5*
 

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