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QUESTION

Find $\ds\int \frac{dx}{\sqrt{x^2+2x}}\,dx$.

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ANSWER


$\ds\int\frac{dx}{\sqrt{x^2+2x}}\,dx
=\int\frac{dx}{\sqrt{(x+1)^2-1^2}}\,dx=\cosh^{-1}(x+1)+c$



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