Limit question. Please help
\[\lim_{x \rightarrow 0} = \frac{ 3^{1/x} - 1 }{ 3^{1/x} +1 }\]
are you allowed to use l'hosptal?
No I unfortunately am not allowed to
ok let me think for a sec then on other ways
Ok thanks
ok and do you know how to differentiate 3^(1/x)?
No I do not
\[x>0 \text{ we have } 3^\frac{1}{x}-1>0 \\ x<0 \text{ we have } 3^\frac{1}{x}-1<0 \\ \text{ for any real } x \neq 0 \text{ we have } 3^\frac{1}{x}+1>0 \]
This should help you to conclude something about the actual limit since this giving you information about the left and right limit.
Like we don't need to know the exact left and right limit just that they differ.
For this question I have to show all the work. How would I show that?
Well I know 3^a is positive for any real a so 3^a+1 is still greater than 0
3^a-1 if a=0 then we have 1-1 but if a<0 then 0<3^a<1 so 3^a-1 will be negative but if a>0 then 3^a>1 so 3^a-1 will be positive
since the left and right limit differ then the actual limit doesn't exist
Okay thanks
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