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Limit to infinity question

  • Thread starter Pyroadept
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  • #1
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Homework Statement



lim_x->∞ of [√x + 2|x|] / [1 + x]

Homework Equations


lim_x->∞ of 1/[x^n] = 0


The Attempt at a Solution


Hi everyone,

Here's what I've done so far:

I divided top and bottom by the highest power of x, i.e. x.
So:
[x^-1/2 +/- 2] / [1/x + 1]

And taking the limit of x to ∞ of this:
[0 +/- 2] / [0 + 1] = +/- 2

Is this correct?

Thanks for any help.
 

Answers and Replies

  • #2
gabbagabbahey
Homework Helper
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Why is there a [itex]\pm[/itex] in your answer?...Surely you recognize that [itex]x[/itex] is positive as it approaches [itex]+\infty[/itex]?
 
  • #3
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Why is there a [itex]\pm[/itex] in your answer?...Surely you recognize that [itex]x[/itex] is positive as it approaches [itex]+\infty[/itex]?
Thanks, I didn't think about that. But is it correct apart from that?
 
  • #4
gabbagabbahey
Homework Helper
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Yes.
 

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