Menu Close

Category: Integration

Prove-that-pi-2-0-ln-1-sint-sint-dt-pi-2-8-1-2-arccos-2-

Question Number 197060 by universe last updated on 07/Sep/23 $$\mathrm{Prove}\:\mathrm{that}\: \\ $$$$\underset{\:\mathrm{0}} {\int}^{\:\frac{\pi}{\mathrm{2}}} \frac{\mathrm{ln}\left(\mathrm{1}+\alpha\mathrm{sin}{t}\right)}{\mathrm{sin}{t}}{dt}=\:\frac{\pi^{\mathrm{2}} }{\mathrm{8}}−\frac{\mathrm{1}}{\mathrm{2}}\left(\mathrm{arccos}\alpha\right)^{\mathrm{2}} \\ $$ Commented by universe last updated on 07/Sep/23 $${question}\:\mathrm{196950}…

Question-196983

Question Number 196983 by universe last updated on 05/Sep/23 Commented by Frix last updated on 06/Sep/23 $$\mathrm{I}\:\mathrm{can}'\mathrm{t}\:\mathrm{solve}\:\mathrm{the}\:\mathrm{first}\:\mathrm{2}\:\mathrm{but}\:\mathrm{wolframalpha}\:\mathrm{can} \\ $$$$\left(\mathrm{C}\:\mathrm{is}\:\mathrm{the}\:\mathrm{Catalan}\:\mathrm{constant}\right) \\ $$$$\mathrm{1}.\:{I}_{\mathrm{1}} =\underset{\mathrm{0}} {\overset{\pi} {\int}}\frac{{x}^{\mathrm{3}} }{…}{dx}=\frac{\pi\left(−\mathrm{1440C}+\mathrm{1144}+\mathrm{15}\pi\left(−\mathrm{41}+\mathrm{20}\pi+\mathrm{24ln}\:\mathrm{2}\right)\right)}{\mathrm{3780}}…

xe-1-2x-dx-

Question Number 196832 by Frix last updated on 01/Sep/23 $$\int{x}\mathrm{e}^{\frac{\mathrm{1}}{\mathrm{2}{x}}} {dx}=? \\ $$ Commented by mokys last updated on 02/Sep/23 $${u}\:=\:\frac{\mathrm{1}}{\mathrm{2}{x}}\:\rightarrow\:{x}\:=\:\frac{\mathrm{1}}{\mathrm{2}{u}}\:\rightarrow\:{dx}\:=\:−\:\frac{{du}}{\mathrm{2}{u}^{\mathrm{2}} } \\ $$$$ \\…

Question-196688

Question Number 196688 by cortano12 last updated on 29/Aug/23 Answered by Frix last updated on 29/Aug/23 $$\int\sqrt{{x}−\sqrt{{x}^{\mathrm{2}} −\mathrm{4}}}\:{dx}\:\overset{{t}=\sqrt{{x}−\sqrt{{x}^{\mathrm{2}} −\mathrm{4}}}} {=} \\ $$$$=\int\frac{{t}^{\mathrm{4}} −\mathrm{4}}{{t}^{\mathrm{2}} }{dt}=\frac{{t}^{\mathrm{3}} }{\mathrm{3}}+\frac{\mathrm{4}}{{t}}=…

Question-196557

Question Number 196557 by BHOOPENDRA last updated on 27/Aug/23 Answered by qaz last updated on 27/Aug/23 $$\int_{\mathrm{0}} ^{{t}} {e}^{−{u}} \mathrm{sin}\:{udu}=−\Im\int_{\mathrm{0}} ^{{t}} {e}^{−\left(\mathrm{1}+{i}\right){u}} {du}=\Im\frac{\mathrm{1}}{\mathrm{1}+{i}}\left({e}^{−\left(\mathrm{1}+{i}\right){t}} −\mathrm{1}\right) \\…

Question-196496

Question Number 196496 by RoseAli last updated on 26/Aug/23 Answered by witcher3 last updated on 26/Aug/23 $$\int\frac{\mathrm{1}}{\mathrm{tg}^{\mathrm{2}} \left(\mathrm{x}\right).\mathrm{cos}^{\mathrm{6}} \left(\mathrm{x}\right)} \\ $$$$=\int\frac{\mathrm{1}+\mathrm{tg}^{\mathrm{2}} \left(\mathrm{x}\right)}{\mathrm{tg}^{\mathrm{2}} \left(\mathrm{x}\right)}.\left(\mathrm{1}+\mathrm{tg}^{\mathrm{2}} \left(\mathrm{x}\right)\right)^{\mathrm{2}} \mathrm{dx}…

Question-196459

Question Number 196459 by RoseAli last updated on 25/Aug/23 Answered by Frix last updated on 25/Aug/23 $$\mathrm{Use}\:\mathrm{Ostrogradski}'\mathrm{s}\:\mathrm{Method}\:\mathrm{to}\:\mathrm{get} \\ $$$$\int\frac{{x}^{\mathrm{4}} +{x}^{\mathrm{2}} +\mathrm{1}}{\left({x}^{\mathrm{2}} +\mathrm{1}\right)^{\mathrm{3}} }{dx}=\frac{{x}\left(\mathrm{2}{x}^{\mathrm{2}} +\mathrm{3}\right)}{\mathrm{2}\left({x}^{\mathrm{2}} +\mathrm{1}\right)}−\frac{\mathrm{1}}{\mathrm{2}}\int\frac{{dx}}{{x}^{\mathrm{2}}…