Question Number 158313 by mnjuly1970 last updated on 02/Nov/21
Answered by mr W last updated on 02/Nov/21
$$\alpha,\beta,\gamma\:{are}\:{angles}\:{of}\:{a}\:{triangle}. \\ $$$${F}=\frac{\mathrm{sin}\:\alpha\:\mathrm{cos}\:\alpha+\mathrm{sin}\:\beta\:\mathrm{cos}\:\beta+\mathrm{sin}\:\gamma\:\mathrm{cos}\:\gamma}{\mathrm{sin}\:\alpha\:\mathrm{sin}\:\beta\:\mathrm{sin}\:\gamma} \\ $$$${F}=\frac{\mathrm{sin}\:\mathrm{2}\alpha+\mathrm{sin}\:\mathrm{2}\beta+\mathrm{sin}\:\mathrm{2}\gamma}{\mathrm{2}\:\mathrm{sin}\:\alpha\:\mathrm{sin}\:\beta\:\mathrm{sin}\:\gamma} \\ $$$${F}=\frac{\mathrm{4}\:\mathrm{sin}\:\alpha\:\mathrm{sin}\:\beta\:\mathrm{sin}\:\gamma}{\mathrm{2}\:\mathrm{sin}\:\alpha\:\mathrm{sin}\:\beta\:\mathrm{sin}\:\gamma} \\ $$$${F}=\mathrm{2} \\ $$
Commented by mnjuly1970 last updated on 02/Nov/21
$${thx}\:{mr}\:\:\:\mathcal{W} \\ $$