Indefinite Integral Question - What kind of substitution?

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I've been trying to solve this integral for the past two hours, but haven't gotten anywhere:

$$ \int \frac {dx}{2\sqrt{x-4}+x} $$

I've tried various kinds of substitutions to no avail. Even just a prod in the right direction would be very helpful.

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Your best best is to start with the substitution $x-4=u^2$ to get

$$\int{2u\,du\over2u+(u^2+4)}=\int{2(u+1)-2\over(u+1)^2+3}du$$

Can you take it from there? (You should get a logarithm and an arctangent in the final answer.)