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Question-154875




Question Number 154875 by mathdanisur last updated on 22/Sep/21
Answered by mindispower last updated on 23/Sep/21
u=log(x+(5/x))  Ω⇔∫e^(2u) sin(u)du
$${u}={log}\left({x}+\frac{\mathrm{5}}{{x}}\right) \\ $$$$\Omega\Leftrightarrow\int{e}^{\mathrm{2}{u}} {sin}\left({u}\right){du} \\ $$
Commented by mathdanisur last updated on 23/Sep/21
thanks Ser, but how
$$\mathrm{thanks}\:\boldsymbol{\mathrm{S}}\mathrm{er},\:\mathrm{but}\:\mathrm{how} \\ $$
Commented by mindispower last updated on 23/Sep/21
u=ln(x+(5/x))⇒du=((1−(5/x^2 ))/(x+(5/x)))dx⇒(1−(5/x^2 ))dx=ue^u du  ∫(x+(5/x))_(=e^u ) sin(ln(x+(5/x))).(1−(5/x^2 ))dx_(=e^u du)   =∫e^u sin(u).e^u du=∫e^(2u) sin(u)du
$${u}={ln}\left({x}+\frac{\mathrm{5}}{{x}}\right)\Rightarrow{du}=\frac{\mathrm{1}−\frac{\mathrm{5}}{{x}^{\mathrm{2}} }}{{x}+\frac{\mathrm{5}}{{x}}}{dx}\Rightarrow\left(\mathrm{1}−\frac{\mathrm{5}}{{x}^{\mathrm{2}} }\right){dx}={ue}^{{u}} {du} \\ $$$$\int\left({x}+\frac{\mathrm{5}}{{x}}\right)_{={e}^{{u}} } {sin}\left({ln}\left({x}+\frac{\mathrm{5}}{{x}}\right)\right).\left(\mathrm{1}−\frac{\mathrm{5}}{{x}^{\mathrm{2}} }\right){dx}_{={e}^{{u}} {du}} \\ $$$$=\int{e}^{{u}} {sin}\left({u}\right).{e}^{{u}} {du}=\int{e}^{\mathrm{2}{u}} {sin}\left({u}\right){du} \\ $$
Commented by mathdanisur last updated on 23/Sep/21
very nise Ser, thank you
$$\mathrm{very}\:\mathrm{nise}\:\boldsymbol{\mathrm{S}}\mathrm{er},\:\mathrm{thank}\:\mathrm{you} \\ $$
Commented by mindispower last updated on 23/Sep/21
withe Pleasur
$${withe}\:{Pleasur} \\ $$

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