Question Number 6131 by love math last updated on 15/Jun/16
$${sin}\:\mathrm{4}{x}+{sin}\mathrm{12}{x}+{sin}\:\mathrm{8}{x} \\ $$
Answered by Irfan hakim last updated on 18/Jun/16
$$\mathrm{sin}\:\mathrm{24}{x} \\ $$
Commented by love math last updated on 19/Jun/16
$${are}\:{you}\:{joking}? \\ $$
Answered by prakash jain last updated on 20/Jun/16
$$\mathrm{sin}\:\mathrm{4}{x}+\mathrm{sin}\:\mathrm{12}{x}=\mathrm{2sin}\:\frac{\mathrm{12}+\mathrm{4}}{\mathrm{2}}{x}\mathrm{cos}\:\frac{\mathrm{12}−\mathrm{4}}{\mathrm{2}}{x} \\ $$$$\mathrm{2sin}\:\mathrm{8}{x}\mathrm{cos}\:\mathrm{4}{x}+\mathrm{sin}\:\mathrm{8}{x} \\ $$$$=\mathrm{sin}\:\mathrm{8}{x}\left(\mathrm{2cos}\:\mathrm{4}{x}+\mathrm{1}\right) \\ $$
Commented by prakash jain last updated on 20/Jun/16
$$\mathrm{Do}\:\mathrm{you}\:\mathrm{need}\:\mathrm{to}\:\mathrm{reduce}\:\mathrm{it}\:\mathrm{to}\:\mathrm{sin}\:{x}? \\ $$