Hi I'm having some trouble with evaluating these limits. I can't figure out what to do. I guess i forgot some calc one. I don't have much work but All I'm asking for for now is a couple hints.(adsbygoogle = window.adsbygoogle || []).push({});

[tex]\lim_{x\rightarrow\infty} \frac{e^{3x} -e^{-3x}}{e^{3x} + e^{-3x}} [/tex]

I tried dividing numerator and denominator by e^3x and 3^-3x Neither worked? Any hints on what else to do?

[tex] \lim_{x\rightarrow2^+} e^{3/(2-x)} [/tex] I have no idea here. Please I know theres not much work but Im totaly lost.

Now the integral:

[tex] \int e^x \sqrt{1+e^x} dx [/tex]

I tried the substitution u = [tex] \sqrt{1+e^x} [/tex]

Using that substitution i get this:

[tex] 2\int u^2 du [/tex]

integrate this and you get:

[tex] (1/2) u^4 + C [/tex]

which is:

(1+ 2e^x +e^2x)/2, This is nowhere near the answer. Where did I go wrong. I don't see why that substitution didn't work.

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# Limits with e^x and an integral too!

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