quickest way to solve..

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quickest way to solve..

by swtmix » Mon Nov 19, 2007 11:17 am
what's the shortcut to solving?

5^12+5^13+5^14?

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by mschling52 » Mon Nov 19, 2007 1:38 pm
Not sure there is really a shortcut...at least I don't see one immediately. You could factor out 5^12, giving you

(5^12)(1+5+25) = 31(5^12)

Then, I expressed 5^12 = 25^6 = 625^3.

From there I multiplied out 625*625*625 and multiplied the result by 31. This does take a minute or two to do by hand, so there may be an easier way, but I am not seeing it.

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by beatthegmat » Mon Nov 19, 2007 1:59 pm
Moved to PS forum area.
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