Category: Trigonometry

Question Number 75209 by vishalbhardwaj last updated on 08/Dec/19 Answered by Kunal12588 last updated on 08/Dec/19 $$x+y+z=xyz$$$$letx=tan\alpha ,y=tan\beta ,z=tan\gamma$$$$tan\alpha +tan\beta +tan\gamma =tan\alpha tan\beta tan\gamma$$$$\Rightarrow tan\gamma (1-tan\alpha tan\beta )=-(tan\alpha +tan\beta )$$$$\Rightarrow{tan}\:\gamma=−\frac{{tan}\:\alpha+{tan}\beta}{\mathrm{1}−{tan}\:\alpha\:{tan}\:\beta}=−{tan}\:\left(\alpha+\beta\right)…

Question Number 9594 by tawakalitu last updated on 19/Dec/16 Answered by sandy_suhendra last updated on 20/Dec/16 Commented by tawakalitu last updated on 20/Dec/16 $$\mathrm{God}\:\mathrm{bless}\:\mathrm{you}\:\mathrm{sir}. \…

Question Number 9589 by tawakalitu last updated on 19/Dec/16 Answered by ridwan balatif last updated on 19/Dec/16 Commented by tawakalitu last updated on 19/Dec/16 $$\mathrm{i}\:\mathrm{really}\:\mathrm{appreciate}\:\mathrm{sir}.\:\mathrm{God}\:\mathrm{bless}\:\mathrm{you}.…

Question Number 9525 by Joel575 last updated on 12/Dec/16 $$\mathrm{If}{x}_1,x_2,x_3,\dots ,x_{2009}\in \mathbb{R}$$$$\mathrm{Find}\mathrm{the}\mathrm{minimum}\mathrm{value}\mathrm{from}$$$$\left(\mathrm{cos}\:{x}_{\mathrm{1}} \right)\left(\mathrm{sin}\:{x}_{\mathrm{2}} \right)\:+\:\left(\mathrm{cos}\:{x}_{\mathrm{2}} \right)\left(\mathrm{sin}\:{x}_{\mathrm{3}} \right)\:+\:…\:+\:\left(\mathrm{cos}\:{x}_{\mathrm{2008}} \right)\left(\mathrm{sin}\:{x}_{\mathrm{2009}} \right)\:+\:\left(\mathrm{cos}\:{x}_{\mathrm{2009}} \right)\left(\mathrm{sin}\:{x}_{\mathrm{1}}…

Question Number 75048 by mathocean1 last updated on 06/Dec/19 $$\mathrm{I}\mathrm{would}\mathrm{like}\mathrm{that}\mathrm{you}\mathrm{help}\mathrm{me}\mathrm{to}$$$$\mathrm{show}\mathrm{this}\mathrm{equality}:$$$$16\cos \frac{\mathrm{\Pi }}{24}\cos \frac{5\mathrm{\Pi }}{24}\cos \frac{7\mathrm{\Pi }}{24}\cos \frac{11\mathrm{\Pi }}{24}=1$$ Commented by mind is power last updated on 06/Dec/19…