Algebraic manipulation of integral

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SUMMARY

The integral \int_0^{\frac{\pi}{2}} \frac{\cos(x)}{1+\sin^2(x)} \ln(1+\cos(x))\ dx can be simplified through a substitution of y=\sin(x), leading to the expression \int_0^1 \frac{\arctan(y)}{y\sqrt{1-y^2}}\ dy - \int_0^1 \frac{\arctan{y}}{y}\ dy. The first integral is derived from prior knowledge, while the second integral evaluates to Catalan's constant. This manipulation showcases the effectiveness of algebraic techniques in solving complex integrals.

PREREQUISITES
  • Understanding of integral calculus and substitution methods
  • Familiarity with the properties of logarithmic functions
  • Knowledge of arctangent function and its integral
  • Concept of Catalan's constant and its significance in mathematics
NEXT STEPS
  • Study the properties and applications of Catalan's constant
  • Learn about integration techniques involving logarithmic functions
  • Explore the use of partial integration in solving integrals
  • Investigate advanced substitution methods in integral calculus
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Students and educators in mathematics, particularly those focused on integral calculus and algebraic manipulation techniques.

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Homework Statement



<br /> \int_0^{\frac{\pi}{2}} \frac{\cos(x)}{1+\sin^2(x)} \ln(1+\cos(x))\ dx<br />


The Attempt at a Solution


Can anyone give me a hint as to what to do?
 
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Using y=sin(x) followed by partial integration and some algebraic manipulation you can get to the following integral:

\int_0^1 \frac{\arctan(y)}{y\sqrt{1-y^2}}\ dy - \int_0^1 \frac{\arctan{y}}{y}\ dy

You know the first integral from a previous question you asked and the second integral is equal to Catalan's constant.
 

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