Finite Limit Problem: Understanding cosx/x^0 = 1

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lukatwo
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Homework Statement



I've read in my textbook, and confirmed via WolframAlpha that lim x->0 (cosx/x^0) =1 , and need an explanation for it. I thought it should be ∞ or something undefined, since 0^0 is undefined.

Homework Equations


The Attempt at a Solution



I tried to use L'Hospitale on the expression, but that led to nowhere. There's no intermediate step between the expression and solution in both textbook, and Wolfram.
 
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lukatwo said:

Homework Statement



I've read in my textbook, and confirmed via WolframAlpha that lim n->0 (cosx/x^0) =1
Typo?
There is no n in your limit expression.

Is this the limit?
$$\lim_{x \to 0} \frac{cos(x)}{x^0} $$
lukatwo said:
, and need an explanation for it. I thought it should be ∞.

Homework Equations





The Attempt at a Solution



I tried to use L'Hospitale on the expression, but that led to nowhere. There's no intermediate step between the expression and solution in both textbook, and Wolfram.
 
It was a typo. Fixed, and yes that is the limit i was referring to!
 
From all this my guess will be 1, but still not clear why. Is it because lim x->0 means that x !=0 but rather close to 0? Meaning some infinitesimal number ^0=1? Am i getting that correctly?
 
lukatwo said:
From all this my guess will be 1, but still not clear why. Is it because lim x->0 means that x !=0 but rather close to 0? Meaning some infinitesimal number ^0=1? Am i getting that correctly?
Yes to both questions. The graph of y = x0 is a horizontal line with a hole at (0, 1).
 
I understand now! Thank you very much for your help!