Need help with comparison method for improper integral?

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SUMMARY

The discussion focuses on applying the comparison method to evaluate the improper integral \(\int \frac{\arctan(x)}{2+e^x}dx\) over the interval from 0 to infinity. The user struggles to identify a suitable function for comparison but is guided to use the inequality \(\frac{\arctan(x)}{2 + e^{x}} < \frac{2}{2 + e^{x}}\), which holds true for all \(x\). This comparison allows for the application of the comparison test to determine the convergence of the integral.

PREREQUISITES
  • Understanding of improper integrals
  • Familiarity with the comparison test in calculus
  • Knowledge of the arctangent function and its properties
  • Basic exponential function behavior
NEXT STEPS
  • Study the comparison test for improper integrals in detail
  • Explore properties of the arctangent function and its limits
  • Learn about convergence criteria for improper integrals
  • Practice with additional examples of improper integrals using comparison methods
USEFUL FOR

Students studying calculus, particularly those focusing on improper integrals and comparison methods, as well as educators looking for teaching strategies in integral calculus.

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Homework Statement


\int \frac{arctan(x)}{2+e^x}dx
where the interval of the integrand is from 0 to infinity.

In order to use the comparison method I need to compare 2 functions but I am having so much difficulty figuring out what function to compare it to.

Its not just this particular question, any question asking to use comparison method, I can't seem to figure out the function to compare it to.

Can I get some tips to finding a function to compare it to?
 
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tan-1(x) < 2 for all x, so therefore...

\frac{tan^{-1}(x)}{2 + e^{x}} &lt; \frac{2}{2 + e^{x}}

for all x (Since 2+ex is never 0, one doesn't have to worry about division by zero.)

So try using the comparison test with that.
 

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