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anonymous
 one year ago
Please help
anonymous
 one year ago
Please help

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anonymous
 one year ago
Best ResponseYou've already chosen the best response.0\[\lim_{x \rightarrow 2}(\sqrt{x+2}\sqrt{2x})\div(x^22x)\]

welshfella
 one year ago
Best ResponseYou've already chosen the best response.0direct substitution gives 0/0 i would apply l'hopitals rule

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0I haven't learned about that

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0this week we just learned about intro to limits

phi
 one year ago
Best ResponseYou've already chosen the best response.0one thought is to multiply top and bottom by \( \sqrt{x+2}+ \sqrt{2x} \)

welshfella
 one year ago
Best ResponseYou've already chosen the best response.0ok so we need to find different way

phi
 one year ago
Best ResponseYou've already chosen the best response.0the top is a difference of squares

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0dw:1438036441844:dw

phi
 one year ago
Best ResponseYou've already chosen the best response.0and don't multiply out the bottom you should get \[ \frac{ (x+2)  2x} { x(x2)(\sqrt{x+2}+\sqrt{2x})} \]

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0@phi did you multiply the whole equation by the conjugate?

phi
 one year ago
Best ResponseYou've already chosen the best response.0the top was (ab)(a+b) = a^2  b^2 where a and b are the square roots the bottom , I just show the multiplication

phi
 one year ago
Best ResponseYou've already chosen the best response.0I can't tell what you did , but it looks too complicated to be right.

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0yes, please. I get where you said that they're difference of squares. But I don't get which factor did you multiply the whole equation to get that result

phi
 one year ago
Best ResponseYou've already chosen the best response.0\[ \frac{(\sqrt{x+2}\sqrt{2x})}{(x^22x)} \\\frac{(\sqrt{x+2}\sqrt{2x})}{x(x2)} \] (factored the bottom, hopefully something cancels...

phi
 one year ago
Best ResponseYou've already chosen the best response.0\[ \frac{(\sqrt{x+2}\sqrt{2x})}{x(x2)} \cdot \frac{(\sqrt{x+2}+\sqrt{2x})}{(\sqrt{x+2}+\sqrt{2x})}\]

phi
 one year ago
Best ResponseYou've already chosen the best response.0it is easier to see the pattern if we call the first term a and the second b then we have (ab)(a+b) which we know (right?) is a^2  b^2

phi
 one year ago
Best ResponseYou've already chosen the best response.0or you can FOIL it out. either way the top becomes \[ (\sqrt{x+2})^2  ( \sqrt{2x})^2 \\ x+2  2x \\ 2x \] or (x2)

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0okay, I got this part.

phi
 one year ago
Best ResponseYou've already chosen the best response.0so we now have the limit of \[ \frac{(x2)}{x(x2)(\sqrt{x+2}+\sqrt{2x})}\]

phi
 one year ago
Best ResponseYou've already chosen the best response.0as long as x is not *exactly* 2 , we can cancel (x2) from top and bottom then we can take the limit

anonymous
 one year ago
Best ResponseYou've already chosen the best response.0OMG, thank you so much. I really learned everything
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