Question Number 97680 by bemath last updated on 09/Jun/20 Commented by bobhans last updated on 09/Jun/20 $$\mathrm{cos}\:\mathrm{6A}−\mathrm{cos}\:\mathrm{2A}=−\mathrm{2sin}\:\mathrm{4Asin}\:\mathrm{2A} \\ $$$$\Leftrightarrow−\mathrm{2sin}\:\mathrm{4Asin}\:\mathrm{2A}−\mathrm{2cos}\:\mathrm{4A}+\mathrm{2}= \\ $$$$\Leftrightarrow\:−\mathrm{4sin}\:^{\mathrm{2}} \mathrm{2A}\:\mathrm{cos}\:\mathrm{2A}−\mathrm{2}\left(\mathrm{1}−\mathrm{2sin}\:^{\mathrm{2}} \mathrm{2A}\right)+\mathrm{2} \\ $$$$\Leftrightarrow−\mathrm{4sin}\:^{\mathrm{2}}…
Question Number 97546 by bobhans last updated on 08/Jun/20 Commented by bobhans last updated on 08/Jun/20 can anyone translate to english? Commented by bemath last updated on 08/Jun/20 $$\mathrm{i}\:\mathrm{don}'\mathrm{t}\:\mathrm{understand}\:…
Question Number 163020 by amin96 last updated on 03/Jan/22 $$\boldsymbol{\mathrm{cos}}^{\mathrm{2}\boldsymbol{\mathrm{n}}} \left(\boldsymbol{\mathrm{x}}\right)+\boldsymbol{\mathrm{sin}}^{\mathrm{2}\boldsymbol{\mathrm{n}}} \left(\boldsymbol{\mathrm{x}}\right)=\frac{\mathrm{4}^{\boldsymbol{\mathrm{n}}} +\mathrm{1}}{\mathrm{5}^{\boldsymbol{\mathrm{n}}} } \\ $$$$\boldsymbol{\mathrm{prove}}\:\boldsymbol{\mathrm{that}} \\ $$ Commented by amin96 last updated on 03/Jan/22…
Question Number 97346 by bobhans last updated on 07/Jun/20 Answered by john santu last updated on 07/Jun/20 $$\mathrm{1}+\mathrm{3}\:\sqrt[{\mathrm{3}\:}]{\mathrm{2}}\:\sqrt[{\mathrm{3}\:\:}]{\left(\mathrm{sin}\:\mathrm{xcos}\:\mathrm{x}\right)^{\mathrm{2}} }\:=\:\mathrm{2} \\ $$$$\mathrm{3}\:\sqrt[{\mathrm{3}\:\:}]{\mathrm{2}}\:\sqrt[{\mathrm{3}\:\:}]{\frac{\mathrm{1}}{\mathrm{4}}\mathrm{sin}^{\mathrm{2}} \:\mathrm{2x}}=\:\mathrm{1} \\ $$$$\mathrm{54}\:\left(\frac{\mathrm{1}}{\mathrm{4}}\mathrm{sin}\:^{\mathrm{2}} \:\mathrm{2x}\right)\:=\:\mathrm{1}…
Question Number 31808 by Abadon last updated on 15/Mar/18 $$\mathrm{The}\:\mathrm{numeric}\:\mathrm{value}\:\mathrm{of}\:\mathrm{the}\:\mathrm{expression}\:\mathrm{is}: \\ $$$$ \\ $$$$\frac{\mathrm{Sec}\:\mathrm{1320}°}{\mathrm{2}}\:−\:\mathrm{2}\:\centerdot\:\mathrm{cos}\:\left(\frac{\mathrm{53}\pi}{\mathrm{3}}\right)\:+\:\left(\mathrm{tg}\:\mathrm{2220}°\right)^{\mathrm{2}} \\ $$ Commented by Tinkutara last updated on 15/Mar/18 1 Commented…
Question Number 162872 by amin96 last updated on 01/Jan/22 Commented by amin96 last updated on 01/Jan/22 $$\boldsymbol{{PROVE}}\:\:\:\:\:\boldsymbol{{THAT}} \\ $$ Answered by Ar Brandon last updated…
Question Number 31745 by pieroo last updated on 13/Mar/18 $$\mathrm{pls},\:\mathrm{why}\:\mathrm{is}\:\mathrm{cos}^{\mathrm{4}} −\mathrm{sin}^{\mathrm{4}\:} \:=\:\mathrm{cos}^{\mathrm{2}} −\mathrm{sin}^{\mathrm{2}} ? \\ $$ Answered by Tinkutara last updated on 13/Mar/18 $$\mathrm{cos}^{\mathrm{4}} \:\theta−\mathrm{sin}^{\mathrm{4}}…
Question Number 162776 by john_santu last updated on 01/Jan/22 $$\:\:\:\frac{\mathrm{sin}\:{x}}{\mathrm{1}−\mathrm{cos}\:{x}}\:=\:\frac{\mathrm{1}}{\mathrm{2}}\: \\ $$$$\:{x}=? \\ $$ Answered by bobhans last updated on 01/Jan/22 $$\:\:\:\mathrm{2sin}\:\mathrm{x}\:+\:\mathrm{cos}\:\mathrm{x}\:=\:\mathrm{1}\: \\ $$$$\:\:\sqrt{\mathrm{5}}\:\left(\frac{\mathrm{2}}{\:\sqrt{\mathrm{5}}}\:\mathrm{sin}\:\mathrm{x}\:+\:\frac{\mathrm{1}}{\:\sqrt{\mathrm{5}}}\:\mathrm{cos}\:\mathrm{x}\right)=\:\mathrm{1} \\…
Question Number 31679 by pieroo last updated on 12/Mar/18 $$\mathrm{prove}\:\mathrm{that}\:\mathrm{sec}^{\mathrm{2}} \theta\:\mathrm{cosec}^{\mathrm{2}} \theta\:=\mathrm{sec}^{\mathrm{2}} \theta+\mathrm{cosec}^{\mathrm{2}} \theta \\ $$ Answered by Tinkutara last updated on 12/Mar/18 $$\mathrm{sec}^{\mathrm{2}} \:\theta\mathrm{cosec}^{\mathrm{2}}…
Question Number 162649 by tounghoungko last updated on 31/Dec/21 $$\:\mathrm{sin}\:^{\mathrm{10}} \left({x}\right)+\mathrm{cos}\:^{\mathrm{10}} \left({x}\right)=\frac{\mathrm{11}}{\mathrm{36}} \\ $$$$\:\mathrm{sin}\:^{\mathrm{12}} \left({x}\right)+\mathrm{cos}\:^{\mathrm{12}} \left({x}\right)=? \\ $$ Answered by Ar Brandon last updated on…