Is Finding a Common Denominator Necessary for Evaluating This Limit?

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How do I evaluate this limit I have no Idea, I'm sorry for not showing my work please!

limx[itex]\rightarrow[/itex]0 [itex]\frac{1}{sin<sup>2</sup>x}[/itex] +[itex]\frac{1}{x<sup>2</sup>}[/itex]
 
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Doesn't it go to infinity?
 


What happens when you have...

[itex]lim_{x\to 0^+} \frac {1}{x}[/itex]

That is a basic limit, answering that should lead you to what you want.
 


When using itex, you wouldn't use the other tags that the board uses such as for superscripts; you would use ^ to make exponents.

Could you have meant this limit with subtraction instead?
[itex]\lim_{x\to 0}\frac{1}{\sin^2x} - \frac{1}{x^2}[/itex]
 
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Lizwi said:
How do I evaluate this limit I have no Idea, I'm sorry for not showing my work please!

[tex]\lim_{x\to 0}\left(\frac{1}{sin^2x}+\frac{1}{x^2}\right)[/tex]


I already edited your post above. Now read the other posts.

DonAntonio
 


I have not taken calc yet, but would he need to find a common denominator?
 


ME_student said:
I have not taken calc yet, but would he need to find a common denominator?


Kudos for the courage to post without having yet studied calculus..:) In this case it isn't needed to find

common denominator as: (1) both parts of the expression are positive, (2) it's a sum and (3) both tend to [itex]\infty[/itex] as [itex]x\to 0[/itex]

DonAntonio