Integral Help: 1/((4x^2)+(4x)+5)

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Homework Statement



Integrate the indefinite integral of 1/((4x^2)+(4x)+5)

Homework Equations





The Attempt at a Solution

 
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tmclary said:

Homework Statement



Integrate the indefinite integral of 1/((4x^2)+(4x)+5)
I assume you mean find the indefinite integral. You also forgot to fill in the following two sections, in particular the final one:
tmclary said:

The Attempt at a Solution

 
Sorry, I have no clue how to get started. The denominator won't factor (at least to linear factors w/ integral coefficients) and the discriminant is complex anyway. So if it's a partial fraction type solution, how do you get started? Thanks.
 
Try completing the square of the denominator.
 
So 1/(4x^2)+4x+5 =1/((2x+1)^2)+4 and I make a u-sub. Looks like tan^-1 type integral. Correct?
 
tmclary said:
So 1/(4x^2)+4x+5 =1/((2x+1)^2)+4 and I make a u-sub. Looks like tan^-1 type integral. Correct?
Looks good to me :approve:. Choose your substitution carefully.
 
Thanks for your help, Def & Hoot!
 
tmclary said:
Thanks for your help, Def & Hoot!
A pleasure :smile:
 
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