Category: Trigonometry

Question Number 39388 by maxmathsup by imad last updated on 05/Jul/18 $$calculateA=tan\left(\frac{\pi }{5}\right).tan\left(\frac{2\pi }{5}\right).tan\left(\frac{3\pi }{5}\right).tan\left(\frac{4\pi }{5}\right)$$ Answered by tanmay.chaudhury50@gmail.com last updated on 06/Jul/18 $$tan36.tan72.tan108.tan144$$$${tan}\mathrm{108}={tan}\left(\mathrm{180}−\mathrm{72}\right)=−{tan}\mathrm{72} \…

Question Number 170448 by libaolin last updated on 24/May/22 $$\tan 90°=$$ Commented by mokys last updated on 24/May/22 $$undefind$$ Terms of Service…

Question Number 104904 by bemath last updated on 24/Jul/20 $$4\cos {}^{2}x\sin x-2\sin {}^{2}x=3\sin x$$$$where-\frac{\pi }{2}⩽x⩽\frac{\pi }{2}$$ Answered by bramlex last updated on 24/Jul/20 $$\mathrm{sin}\:{x}\:\left(\mathrm{4cos}\:^{\mathrm{2}} {x}−\mathrm{2sin}\:{x}−\mathrm{3}\right)\:=\:\mathrm{0}…

Question Number 170371 by cortano1 last updated on 22/May/22 $$solve\frac{\sin (x+18°)}{\sin x}=\frac{\sin 18°}{\sin 12°}$$ Answered by greougoury555 last updated on 22/May/22 $$\sin 18°=2\sin 12°\sin 48°$$$$\frac{\sin (x+18°)}{\sin x}=\frac{2\sin 12°\sin 48°}{\sin 12°}$$$$\mathrm{sin}\:\left({x}+\mathrm{18}°\right)=\mathrm{2sin}\:{x}\:\mathrm{sin}\:\mathrm{48}° \…

Question Number 104735 by bemath last updated on 23/Jul/20 Commented by 1549442205PVT last updated on 23/Jul/20 $$\mathbf{what}\mathbf{is}\mathbf{your}\mathbf{question}?$$ Commented by bemath last updated on…