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Category: Integration

let-I-0-e-x-cos-2-pi-x-dx-and-J-0-e-x-sin-2-pi-x-dx-1-calculate-I-J-and-I-J-2-find-the-values-of-I-and-J-

Question Number 37815 by prof Abdo imad last updated on 17/Jun/18 $${let}\:{I}\:\:=\:\int_{\mathrm{0}} ^{\infty} \:\:{e}^{−{x}} \:{cos}^{\mathrm{2}} \left(\pi\left[{x}\right]\right){dx}\:{and} \\ $$$${J}\:=\:\int_{\mathrm{0}} ^{\infty} \:\:{e}^{−{x}} \:{sin}^{\mathrm{2}} \left(\pi\left[{x}\right]\right){dx} \\ $$$$\left.\mathrm{1}\right)\:{calculate}\:{I}\:+{J}\:\:{and}\:{I}\:−{J} \\…

E-pi-0-a-2-sin-2-a-2-x-2-2ax-cos-d-If-a-gt-x-show-that-E-a-2-x-

Question Number 168872 by MikeH last updated on 20/Apr/22 $${E}=\underset{\mathrm{0}} {\int}^{\pi} \left[\frac{{a}^{\mathrm{2}} \sigma\:\mathrm{sin}\:\theta}{\mathrm{2}\epsilon\sqrt{{a}^{\mathrm{2}} −{x}^{\mathrm{2}} −\mathrm{2}{ax}\:\mathrm{cos}\theta}}\right]{d}\theta \\ $$$$\mathrm{If}\:{a}>{x}\:\mathrm{show}\:\mathrm{that}\:{E}\:=\:\frac{{a}^{\mathrm{2}} \sigma}{\epsilon{x}} \\ $$ Commented by Tinku Tara last…

Question-168857

Question Number 168857 by Sotoberry last updated on 19/Apr/22 Answered by MJS_new last updated on 20/Apr/22 $$\int\frac{\mathrm{1}}{{x}^{\mathrm{3}} }\sqrt{\frac{{x}^{\mathrm{2}} −\mathrm{1}}{{x}+\mathrm{1}}}{dx}=\int\frac{\sqrt{{x}−\mathrm{1}}}{{x}^{\mathrm{3}} }{dx}= \\ $$$$\:\:\:\:\:\left[{t}=\sqrt{{x}−\mathrm{1}}\:\rightarrow\:{dx}=\mathrm{2}\sqrt{{x}−\mathrm{1}}{dt}\right] \\ $$$$=\mathrm{2}\int\frac{{t}^{\mathrm{2}} }{\left({t}^{\mathrm{2}}…