Question Number 181853 by SEKRET last updated on 01/Dec/22
$$\: \\ $$$$\int\:\boldsymbol{\mathrm{cos}}^{−\mathrm{1}} \left(\boldsymbol{\mathrm{tan}}^{\mathrm{3}} \left(\boldsymbol{\mathrm{tan}}\left(\boldsymbol{\mathrm{x}}\right)\right)\right)\:\boldsymbol{\mathrm{dx}}=\:? \\ $$$$ \\ $$$$ \\ $$$$ \\ $$
Commented by SEKRET last updated on 01/Dec/22
$$\boldsymbol{\mathrm{can}}\:\boldsymbol{\mathrm{you}}\:\boldsymbol{\mathrm{say}}\:\boldsymbol{\mathrm{something}} \\ $$
Commented by Frix last updated on 01/Dec/22
$$\mathrm{The}\:\mathrm{answer}\:\mathrm{is}\:\mathrm{secret}.\:\mathrm{Top}\:\mathrm{secret}. \\ $$
Commented by SEKRET last updated on 01/Dec/22
$$\:\boldsymbol{\mathrm{have}}\:\boldsymbol{\mathrm{you}}\:\boldsymbol{\mathrm{seen}}\:\boldsymbol{\mathrm{before}} \\ $$