Question Number 21815 by gopikrishnan005@gmail.com last updated on 04/Oct/17
$${sin}\mathrm{18}^{\mathrm{0}} = \\ $$
Commented by Tinkutara last updated on 04/Oct/17
$$\frac{\sqrt{\mathrm{5}}−\mathrm{1}}{\mathrm{4}} \\ $$
Commented by math solver last updated on 05/Oct/17
$${emmm}\:.\:\: \\ $$$${use}\:{identity}\:\:\mathrm{sin}\:\mathrm{3}{A}=\mathrm{3sin}\:{A}−\mathrm{4sin}\:^{\mathrm{3}} {A} \\ $$