Question Number 35216 by abdo.msup.com last updated on 16/May/18
$${study}\:{the}\:{function}\: \\ $$$${f}_{{n}} \left({x}\right)={arcos}\left({ncosx}\right)\:{n}\geqslant\mathrm{1}\:{integr}. \\ $$
study-the-function-f-n-x-arcos-ncosx-n-1-integr-