h ( x ) = ∫ 2 1 / x arctan ( t ) d t {\displaystyle h(x)=\int _{2}^{1/x}\arctan(t)dt}
d d x [ h ( x ) ] = d d x [ ∫ 2 1 / x arctan ( t ) d t ] < m a t h > − 1 x 2 ( arctan ( 1 x ) − 0 {\displaystyle {\frac {d}{dx}}\left[h(x)\right]={\frac {d}{dx}}\left[\int _{2}^{1/x}\arctan(t)dt\right]<math>{\frac {-1}{x^{2}}}\left(\arctan({\frac {1}{x}}\right)-0}
![{\displaystyle {\frac {d}{dx}}\left[h(x)\right]={\frac {d}{dx}}\left[\int _{2}^{1/x}\arctan(t)dt\right]<math>{\frac {-1}{x^{2}}}\left(\arctan({\frac {1}{x}}\right)-0}](https://en.wikipedia.org/api/rest_v1/media/math/render/svg/b4a9f0786500550e0c4ff7c3200b1b67f2a83218)