Question Number 157452 by tounghoungko last updated on 23/Oct/21
$$\:{solve}\:\mathrm{tan}\:{x}=\mathrm{cos}\:\mathrm{3}{x}\: \\ $$
Commented by MJS_new last updated on 23/Oct/21
$$\mathrm{no}\:\mathrm{useable}\:\mathrm{exact}\:\mathrm{solution}\:\mathrm{possible}\:\Rightarrow\:\mathrm{you} \\ $$$$\mathrm{must}\:\mathrm{approximate} \\ $$