How Does L'Hopital's Rule Apply to Lim (1/x)^tan(x) as x Approaches 0?

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felipe oteiza
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l'hopital must be apply, i'll be very grateful
 
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Hello felipe :welcome:

Do you know the limit for ##\sin x \over x ## ?
 
oops, sorry, you mean $$x^{-\tan x}\ \ ?$$
 
BvU said:
oops, sorry, you mean $$x^{-\tan x}\ \ ?$$
yes! the last
 
Where does ##\ x^{\tan x}\ ## go for ## \ x\downarrow 0 ## ?
 
BvU said:
Where does ##\ x^{\tan x}\ ## go for ## \ x\downarrow 0 ## ?
lim ( 1/x )^tan x as x->0
 
BvU said:
Yes, that was my question :smile:
I don't understand your question :frown: (my english is not very good)
 
What is the limit ##\ \ \displaystyle \lim_{x\downarrow 0}
\ x^{\tan x}\ ## ?
 
tanx ~ x as x ->0, so problem can be looked at as [itex]\lim_{x-->0} x^x[/itex] However [itex]x^x=e^{xlnx}[/itex].
Since [itex]\lim_{x->0}xlnx=0[/itex], the final answer = 1.
 
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mathman said:
tanx ~ x as x ->0, so problem can be looked at as [itex]\lim_{x-->0} x^x[/itex] However [itex]x^x=e^{xlnx}[/itex].
Since [itex]\lim_{x->0}xlnx=0[/itex], the final answer = 1.
thanks
 
shaztp said:
Tan (0)=0 there for answer will be 1
Not by itself. The function is [itex](\frac{1}{x})^{tanx}[/itex], so as x->0, the expression becomes [itex](\frac{1}{0})^{0}[/itex] which is indeterminate.
 
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