|
|
$I=\int\limits_{1}^{e}\frac{3x\ln x+x+\ln x+3}{\sqrt{x\ln x+1} }dx $
$I=\int\limits_{1}^{e}\frac{2(x\ln x+1)+\ln x+x+\ln x+1}{\sqrt{x\ln x+1} }dx $
$I=\int\limits_{1}^{e}\left[ {2\sqrt{x\ln x+1}+\frac{(\ln x +1)(x+1)}{\sqrt{x\ln x+1} }} \right]dx $
$I=\int\limits_{1}^{e}\left[ {2\sqrt{x\ln x+1}+(x+1)\frac{\ln x +1}{\sqrt{x\ln x+1} }} \right]dx $
$I=\int\limits_{1}^{e}\left[ {2(x+1)'\sqrt{x\ln x+1}+(x+1)\sqrt{x\ln x+1}'} \right]dx $
$I=\int\limits_{1}^{e}\left[ {2(x+1)'\sqrt{x\ln x+1}+2(x+1)\sqrt{x\ln x+1}'} \right]dx $
$I=\int\limits_{1}^{e}\left[ {2(x+1)\sqrt{x\ln x+1}} \right]'dx $
$I= {2(x+1)\sqrt{x\ln x+1}} |_1^e $
$I=\boxed{\displaystyle{2\sqrt[3]{(1+e)^2}-4}} $
|