Integrate: \frac{2x+1}{x^2+1} - Solutions

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Homework Statement


Compute the following antiderivative \int \frac {(2x+1)}{ (x^2+1)} d \ x

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The Attempt at a Solution


I tried a method using using substitution of u = x^2+1, but i think this is approaching the question in the complete wrong way. I think maybe some kind of trigonometric function comes into it but I'm not sure which. Thanks in advance for any assistance
 
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tunabeast said:
I tried a method using using substitution of u = x^2+1, but i think this is approaching the question in the complete wrong way. I think maybe some kind of trigonometric function comes into it but I'm not sure which.

Both are needed, but only after you split the fraction

\frac {(2x+1)}{ (x^2+1)} as \frac {2x}{ (x^2+1)} + \frac {1}{ (x^2+1)}
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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