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Category: Trigonometry

Question-94523

Question Number 94523 by peter frank last updated on 19/May/20 Commented by PRITHWISH SEN 2 last updated on 19/May/20 $$\mathrm{By}\:\mathrm{Napier}'\mathrm{s}\:\mathrm{Analogy}\: \\ $$$$\mathrm{for}\:\mathrm{any}\bigtriangleup\mathrm{ABC} \\ $$$$\:\:\:\:\:\:\:\:\boldsymbol{\mathrm{tan}}\frac{\boldsymbol{\mathrm{B}}−\boldsymbol{\mathrm{C}}}{\mathrm{2}}\:=\frac{\boldsymbol{\mathrm{b}}−\boldsymbol{\mathrm{c}}}{\boldsymbol{\mathrm{b}}+\boldsymbol{\mathrm{c}}}\:\boldsymbol{\mathrm{cot}}\frac{\boldsymbol{\mathrm{A}}}{\mathrm{2}} \\…

Question-160050

Question Number 160050 by tounghoungko last updated on 24/Nov/21 Answered by mindispower last updated on 24/Nov/21 $${cos}\left({a}\right)+{cos}\left({b}\right)=\mathrm{2}{cos}\left(\frac{{a}−{b}}{\mathrm{2}}\right){cos}\left(\frac{{a}+{b}}{\mathrm{2}}\right) \\ $$$${sin}\left({a}\right)+\mathrm{sin}\left(\mathrm{b}\right)=\mathrm{2cos}\left(\frac{\mathrm{a}−\mathrm{b}}{\mathrm{2}}\right)\mathrm{sin}\left(\frac{\mathrm{a}+\mathrm{b}}{\mathrm{2}}\right) \\ $$$$\Leftrightarrow\frac{{cos}\left(\mathrm{3}{x}\right)\left(\mathrm{2}{cos}\left(\mathrm{5}{x}\right)+\mathrm{1}\right)}{{cos}\left(\mathrm{3}{x}\right)\left(\mathrm{2}{sin}\left(\mathrm{5}{x}\right)+\mathrm{1}\right)}=\mathrm{1} \\ $$$$\forall{x}\in\mathbb{R}−\left\{{cos}\left(\mathrm{3}{x}\right)=\mathrm{0}\right\} \\ $$$$\Leftrightarrow{sin}\left(\mathrm{5}{x}\right)={cos}\left(\mathrm{5}{x}\right)\:{easy}\:{now}…

if-q-1-sin-then-prove-that-sec-tan-2-1-q-

Question Number 159845 by abdullah_ff last updated on 21/Nov/21 $$\mathrm{if}\:{q}\:=\:\mathrm{1}−{sin}\theta;\:\mathrm{then}\:\mathrm{prove}\:\mathrm{that} \\ $$$$\left({sec}\theta\:−\:{tan}\theta\right)^{\mathrm{2}} \:=\:\frac{\mathrm{1}}{{q}} \\ $$ Commented by tounghoungko last updated on 21/Nov/21 $$\mathrm{sin}\:\theta\:=\:\mathrm{1}−{q}\: \\ $$$$\:\mathrm{cos}\:\theta\:=\sqrt{\mathrm{1}−\left(\mathrm{1}−\mathrm{2}{q}+{q}^{\mathrm{2}}…

if-cos-4-sin-4-2-5cos-then-find-the-value-of-

Question Number 159787 by abdullah_ff last updated on 21/Nov/21 $$\mathrm{if}\:{cos}^{\mathrm{4}} \theta\:−\:{sin}^{\mathrm{4}} \theta\:=\:\mathrm{2}\:−\:\mathrm{5}{cos}\theta \\ $$$$\mathrm{then}\:\mathrm{find}\:\mathrm{the}\:\mathrm{value}\:\mathrm{of}\:\theta \\ $$ Commented by cortano last updated on 21/Nov/21 $$\Rightarrow\:\mathrm{cos}\:^{\mathrm{2}} \theta−\mathrm{sin}\:^{\mathrm{2}}…

If-log-e-tan-3pi-8-prove-that-3-tanh-2-2-2-

Question Number 28708 by tawa tawa last updated on 29/Jan/18 $$\mathrm{If}\:\:\:\theta\:\:=\:\:\mathrm{log}_{\mathrm{e}} \left\{\mathrm{tan}\left(\frac{\mathrm{3}\pi}{\mathrm{8}}\right)\right\}\:,\:\:\:\mathrm{prove}\:\mathrm{that}\:\:\:\:\:\:\:\:\:\:\:\mathrm{3}\:\mathrm{tanh}\left(\mathrm{2}\theta\right)\:=\:\mathrm{2}\sqrt{\mathrm{2}} \\ $$ Terms of Service Privacy Policy Contact: info@tinkutara.com