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How do I evaluate this limit

  1. May 28, 2012 #1
    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}{sin2x}[/itex] +[itex]\frac{1}{x2}[/itex]
  2. jcsd
  3. May 28, 2012 #2
    Re: Limits

    Doesn't it go to infinity?
  4. May 28, 2012 #3
    Re: Limits

    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.
  5. May 28, 2012 #4
    Re: Limits

    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]
    Last edited: May 28, 2012
  6. May 28, 2012 #5
    Re: Limits

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

  7. Jun 2, 2012 #6
    Re: Limits

    I have not taken calc yet, but would he need to find a common denominator?
  8. Jun 2, 2012 #7
    Re: Limits

    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]

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