![Studio della funzione f{{\left({x}\right)}}= \ln{{x}}- \arctan{{\left({x}-{1}\right)}} con commento audio Studio della funzione f{{\left({x}\right)}}= \ln{{x}}- \arctan{{\left({x}-{1}\right)}} con commento audio](https://www.skuola.net/news_foto/2017/09/lnx-arctanx-1.jpg)
Studio della funzione f{{\left({x}\right)}}= \ln{{x}}- \arctan{{\left({x}-{1}\right)}} con commento audio
Dave Richeson on X: "Euler proved that π/4=arctan(1/2)+arctan(1/3), which can be used for computing digits of π (using the arctangent series). I wondered if I could prove it without using a trig
![trigonometry - What is the value of $\arctan(1/2)+\arctan(1/5)+\arctan(1/8)$? - Mathematics Stack Exchange trigonometry - What is the value of $\arctan(1/2)+\arctan(1/5)+\arctan(1/8)$? - Mathematics Stack Exchange](https://i.stack.imgur.com/jKnbo.png)