Help manipulating integral to use arctan or trig-sub methods

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SUMMARY

The integral ∫1/(x²+4)² can be approached using trigonometric substitution methods. The key manipulation involves recognizing that the integral resembles the form ∫dx/(x²+a²) = (1/a)arctan(x/a) + c, where a = 2. To facilitate this, the substitution u = 2tan(θ) is recommended, allowing the integral to be transformed into a solvable form. This approach effectively utilizes trigonometric identities to simplify the integral for further evaluation.

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  • Understanding of integral calculus, specifically techniques for integration.
  • Familiarity with trigonometric identities and substitutions.
  • Knowledge of the arctangent function and its properties.
  • Basic skills in manipulating algebraic expressions for integration.
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Homework Statement


∫1/(x2+4)2

Homework Equations


∫dx/(x2+a2)=(1/a)arctan(x/a)+c

The Attempt at a Solution


This looks like an arctan integral or a trig substitution, but in its current form neither would work without manipulation. I'm mainly looking for how to manipulate it to use one of these methods

Thanks!
 
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cjarnutowski said:

Homework Statement


∫1/(x2+4)2


Homework Equations


∫dx/(x2+a2)=(1/a)arctan(x/a)+c


The Attempt at a Solution


This looks like an arctan integral or a trig substitution, but in its current form neither would work without manipulation. I'm mainly looking for how to manipulate it to use one of these methods

Thanks!
Trig substitution is the way to go here. Do you know the substitution to use?
 
I'm only giving this one hint then it's up to you to complete the rest.

square root (a^2 + u^2)

u = a*tan(theta)
 

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