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help on GCF problem

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help on GCF problem

by emilyg » Sun Sep 27, 2009 5:46 pm
This problem just appeared on one of my practice tests and I didn't know how to answer it.

What is the greatest common factor of 4^17 - 2^28?

Thanks so much for the help!
Emily
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by sunnyjohn » Sun Sep 27, 2009 6:44 pm
IMO:4

4(17 -2*7)

4 is the highest factor.
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by vaibhav.iit2002 » Thu Oct 01, 2009 7:33 am
Its 2^28

4^17 = 2^34
2^34, 2^28 = 2^28x2^6, 2^28

hence GCF is 2^28
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by xcusemeplz2009 » Thu Oct 01, 2009 7:50 am
2^28
It does not matter how many times you get knocked down , but how many times you get up
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by sunnyjohn » Thu Oct 01, 2009 10:01 pm
Oops, I thought its multiplication...
its power...!
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