https://s0.wp.com/latex.php?latex=%5Cdisplaystyle+16%29%5Cint%7B%5Cfrac%7B1%7D%7B1%2B%7B%7Bx%7D%5E%7B2%7D%7D%7D%7Ddx%3DArcTanx%2BC&bg=ffffff&fg=000&s=0&c=20201002