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check
Oct6-04, 09:57 PM
I've can't seem to get this:

\lim_{\substack{x\rightarrow 1}} \frac {\sqrt{x} -
x^2} {1 - \sqrt{x}}

I know it equals 3... I got that from the using numbers close to 1 method and from the dervative of the top over the derivative of the bottom method... trouble is, I don't think that's how he wants us to find the answer because we haven't learned the derivative method yet. :yuck: any help would be awesome.

arildno
Oct6-04, 10:02 PM
Set:
a=\sqrt{x}
Then:
\frac{\sqrt{x}-x^{2}}{1-\sqrt{x}}=a\frac{1-a^{3}}{1-a}
Does that help?

check
Oct6-04, 10:15 PM
YES! Oh sweet, thanks a lot!