Question Number 112248 by 675480065 last updated on 06/Sep/20
$$\int_{−\frac{\pi\:\:\:}{\mathrm{2}}} ^{\frac{\pi}{\mathrm{2}}} \mathrm{cos}^{\mathrm{2019}} \left(\mathrm{x}\right)\mathrm{cos}\left(\mathrm{2020x}\right)\mathrm{dx} \\ $$$$\mathrm{pls}\:\mathrm{help} \\ $$