Category: Trigonometry

Question Number 15267 by Tinkutara last updated on 09/Jun/17 $$\mathrm{In}\mathrm{an}\mathrm{acute}\mathrm{angled}\mathrm{\Delta }ABC,\mathrm{the}$$$$\mathrm{minimum}\mathrm{value}\mathrm{of}\tan A\tan B\tan C\mathrm{is}?$$ Commented by prakash jain last updated on 09/Jun/17 $$A=0.1°,B=89.5°,C=89.5°$$$$\mathrm{tan}\:{A}\mathrm{tan}\:{B}\mathrm{tan}\:{C}=.\mathrm{518}…

Question Number 15263 by Tinkutara last updated on 08/Jun/17 $$\mathrm{The}\mathrm{equation}a\sin x+\cos 2x=2a-7$$$$\mathrm{possesses}\mathrm{a}\mathrm{solution}\mathrm{if}$$$$\left(1\right)a>6$$$$\left(2\right)2⩽a⩽6$$$$\left(3\right)a>2$$$$\left(4\right)a$$ Answered by ajfour…

Question Number 80595 by Power last updated on 04/Feb/20 Commented by Power last updated on 04/Feb/20 $$\mathrm{prove}\mathrm{that}$$ Commented by Power last updated on…

Question Number 80519 by mathocean1 last updated on 03/Feb/20 $$\mathrm{g}\left(x\right)=2{cos}^{2}x+sin\left(2x\right).$$$$g^{\prime }\left(x\right)=\dots \dots \dots .?$$ Commented by mr W last updated on 03/Feb/20 $${g}'\left({x}\right)=\mathrm{2}×\mathrm{2}\:\mathrm{cos}\:{x}\:\left(−\mathrm{sin}\:{x}\right)+\mathrm{cos}\:\left(\mathrm{2}{x}\right)\:\mathrm{2} \…

Question Number 145979 by iloveisrael last updated on 09/Jul/21 $$\sin {}^2\mathrm{x}-4\cos {}^3\mathrm{x}-1=2\cos {}^2\mathrm{x}+2\cos \mathrm{x}-2\cos \mathrm{xsin}{}^2\mathrm{x}$$$$\mathrm{x}=?$$ Answered by Olaf_Thorendsen last updated on 10/Jul/21…