Question Number 197035 by bbbbbbbb last updated on 06/Sep/23
$$\mathrm{tan18}=\boldsymbol{\mathrm{a}}\:\boldsymbol{\mathrm{then}}\:\boldsymbol{\mathrm{find}}\:\boldsymbol{\mathrm{you}}\:\mathrm{tan72}? \\ $$
Answered by som(math1967) last updated on 06/Sep/23
$${tan}\mathrm{72}={cot}\left(\mathrm{90}−\mathrm{72}\right)={cot}\mathrm{18}=\frac{\mathrm{1}}{{a}} \\ $$