Integral of $\int_{f(a)}^{f(b)} \frac{\sqrt{f(x)}}{f'(x)}df(x)$

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I am wondering if it is possible to compute the integral $\int_{f(a)}^{f(b)} \frac{\sqrt{f(x)}}{f'(x)}df(x)$ somehow without expanding $df(x)$. Thanks.

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$$\int_{f(a)}^{f(b)}\frac{\sqrt{f(x)}}{f'(x)}\,\mathrm df(x)=\int_{a}^{b}\frac{\sqrt{f(x)}}{f'(x)}f'(x)\,\mathrm dx=\int_{a}^{b}\sqrt{f(x)}\,\mathrm dx$$ This is not possible in general, though it could be possible if $f(x)$ was 'nice' enough. An example where it is not possible is $f(x)=e^{-x^2}$.