MHB How to Evaluate a Limit Involving Infinity using L'Hopital's Rule

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Petrus
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Hello MHB,
$$\lim_{x->\pm\infty}xe^{\frac{2}{x}}-x$$
I start to divide by x and we know that $$\lim_{x->\pm\infty} \frac{2}{x}=0$$
with other words we get $$1-1=0$$ but that is wrong, how do I do this :confused:

Regards,
$$|\pi\rangle$$
 
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Re: limit

Rewrite: $$\dfrac{e^{2/x}-1}{1/x}$$
 
Re: limit

tkhunny said:
Rewrite: $$\dfrac{e^{2/x}-1}{1/x}$$
Thanks solved it now!:) got 2 as answer now!:)

Regards,
$$|\pi\rangle$$
 
Re: limit

$$x(e^{\frac{2}{x}}-1) = x ( 1+\frac{2}{x}+\frac{2}{x^2}+\mathcal{o}(\frac{1}{x^2})-1 )$$

$$x( \frac{2}{x}+\frac{2}{x^2}+\mathcal{o} (\frac{1}{x^2}) ) = 2+\frac{2}{x}+\mathcal{o} (\frac{1}{x}) $$
 

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