\(\int \frac{f^{'}(x)}{f(x)}dx=\)

\(\log |f(x)|+c\) \(\log |f^{'}(x)|+c\) \(\log |\frac{f(x)}{f^{'}(x)}|+c\) none

\(\log |f(x)|+c\)

Put \(f(x)=t\) $ f'(x) . dx = dt$ $\Rightarrow \int{\frac{dt}{t}} = lnt + C = ln |f(x)| + C$$