Is there an easier way of finding the square root of big....

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Is there an easier way of finding the square root of big numbers?

I've been using the Official Guide and its solutions seem to find the square root of large numbers (i.e. triple digits) out of the bloom, whereas I tend to factor the digits under the root sign.

Is there a trick that I don't know about or is just memorization?
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by VP_Jim » Sun Dec 21, 2008 9:03 am
For me, the easiest way is to factor the number under the root. Other than the perfect squares, it's too time consuming and inefficient to memorize. But, you should know your perfect squares up to 225 (15^2).
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by Emawk » Sun Dec 21, 2008 12:14 pm
Factoring? I thought as much. Thanks, Jim.

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by beastly B » Mon Dec 27, 2010 9:15 pm
Emawk wrote:Is there an easier way of finding the square root of big numbers?

I've been using the Official Guide and its solutions seem to find the square root of large numbers (i.e. triple digits) out of the bloom, whereas I tend to factor the digits under the root sign.

Is there a trick that I don't know about or is just memorization?
how about trying to estimate