Finding the Limit of $\frac {\sqrt{x} - x^2} {1 - \sqrt{x}}$

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The limit of the expression as x approaches 1 is evaluated as follows: lim (x→1) (√x - x²) / (1 - √x). The user initially finds the limit equals 3 using numerical approximation and derivatives, but seeks a method aligned with their current learning. By substituting a = √x, the expression simplifies to a(1 - a³) / (1 - a), which aids in finding the limit. This substitution proves helpful, confirming the limit is indeed 3.
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I've can't seem to get this:

\lim_{\substack{x\rightarrow 1}} \frac {\sqrt{x} - <br /> 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. any help would be awesome.
 
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Set:
a=\sqrt{x}
Then:
\frac{\sqrt{x}-x^{2}}{1-\sqrt{x}}=a\frac{1-a^{3}}{1-a}
Does that help?
 
YES! Oh sweet, thanks a lot!
 
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