Category: Trigonometry

Question Number 42174 by lucha116 last updated on 19/Aug/18 $${cos}^{2}3xcos2x-{cos}^{2}x=0$$ Answered by tanmay.chaudhury50@gmail.com last updated on 19/Aug/18 $$\left(\frac{1+cos6x}{2}\right)cos2x-\left(\frac{1+cos2x}{2}\right)=0$$$${cos}\mathrm{2}{x}+{cos}\mathrm{2}{x}.{cos}\mathrm{6}{x}−\mathrm{1}−{cos}\mathrm{2}{x}=\mathrm{0} \…

Question Number 107672 by bemath last updated on 12/Aug/20 $$\mathrm{♠}\mathcal{B}e\mathcal{M}ath\mathrm{♠}$$$$\frac{4\sin \left(\frac{2\pi }{7}\right)+\sec \left(\frac{\pi }{14}\right)}{\cot \left(\frac{\pi }{7}\right)}?$$ Commented by Her_Majesty last updated on 12/Aug/20 $$2$$ Commented…

Question Number 107534 by bemath last updated on 11/Aug/20 $$\models \mathcal{B}e\mathcal{M}ath\models$$$$\sin {}^{6}x+\cos {}^{6}x=\frac{7}{16};x\in (0,\frac{\pi }{2})$$ Commented by hgrocks last updated on 11/Aug/20 7 and 16 both my favorite numbers ���� Commented…

Question Number 41902 by upadhyayrakhi20@gmail.com last updated on 15/Aug/18 $$\tan 3\theta \tan 2\theta =1$$$$\mathrm{find}\mathrm{the}\mathrm{general}{}^{\mathrm{solution}\dots \dots }$$ Answered by MJS last updated on 15/Aug/18 $$\tan 3\theta \tan 2\theta -1=0$$$$−\mathrm{2}\frac{\mathrm{cos}\:\mathrm{5}\theta}{\mathrm{cos}\:\mathrm{5}\theta\:+\mathrm{cos}\:\theta}=\mathrm{0} \…

Question Number 107364 by bemath last updated on 10/Aug/20 $$⊚\mathcal{BEMATH}⊚$$$$If\tan x+\sec x=b\Rightarrow \cos x=?$$ Answered by bobhans last updated on 10/Aug/20 $$\Rrightarrow \mathbb{BOB}\mathcal{HANS}\Lleftarrow$$$$\frac{\mathrm{tan}\:\mathrm{x}−\mathrm{sec}\:\mathrm{x}}{\mathrm{tan}\:\mathrm{x}−\mathrm{sec}\:\mathrm{x}}\:×\:\mathrm{tan}\:\mathrm{x}+\mathrm{sec}\:\mathrm{x}\:=\:\flat \…