I didn't solve it pls help me

Problem:

Limit x->0+ [(x+e^x)^(1/x)]

Tanks for your interest

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- April 12th 2014, 01:12 AMMathBanditTrouble on my mind
I didn't solve it pls help me

Problem:

Limit x->0+ [(x+e^x)^(1/x)]

Tanks for your interest - April 12th 2014, 01:33 AMromsekRe: Trouble on my mind
find the limit of the natural log of the expression and take the exponential of that limit.

$\ln\left((x+e^x)^{1/x}\right) = \dfrac 1 x \ln(x+e^x)$

Now apply L'Hopital's rule

$f(x)=\ln(x+e^x)$

$g(x)=x$

$f'(x)=\dfrac{1+e^x}{x+e^x}$

$g'(x)=1$

$\displaystyle{\lim_{x \to 0}}\dfrac{f'(x)}{g'(x)}=\dfrac{1+1}{0+1}=2$

Now take the exponential of this to obtain the limit of the original expression.

$\displaystyle{\lim_{x\to 0}}\left((x+e^x)^{1/x}\right) =e^2$ - April 12th 2014, 01:52 AMMathBanditRe: Trouble on my mind
Tanks but we don't know "Taylor series". Have you another solution?

- April 12th 2014, 02:04 AMromsekRe: Trouble on my mind
I editted the solution. I should have used L'Hopital's rule to begin with.

- April 12th 2014, 03:44 AMMathBanditRe: Trouble on my mind
This is it! Tanks a lot :)