Help manipulating integral to use arctan or trig-sub methods

[cjarnutowski]

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!

 

[Mark44]

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?

 

[McAfee]

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)