Calc Limit: \sqrt{x}-3/(x-9) Stuck?

Thread starter Saladsamurai
Start date Sep 13, 2009
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Limit

Sep 13, 2009

Saladsamurai

I don't know why I am stuck on this one?

\lim_{x\rightarrow 9}\frac{\sqrt{x}-3}{x-9}

I tried multiplying by the conjugate of both the Numerator, and then the denominator. Is there another 'trick' like that?

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Sep 13, 2009

njama

Do a little substitution. What if x=t² ?

Sep 13, 2009

rarkup

Try using the x² - y² = (x + y)(x - y) pattern on the denominator first.

Sep 13, 2009

Saladsamurai

Thanks!

Last edited by a moderator: Apr 24, 2017

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