v – u at least

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v – u at least

by sanju09 » Tue May 18, 2010 5:07 am
If x is a positive integer, is the value of v - u at least twice the value of 3^x - 2^x?
(1) u = 2^x + 1 and v = 3^x + 1.
(2) x = 3.
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by thinkpanther » Tue May 18, 2010 10:30 am
IMO A

1) v = 3^x + 1 ; u = 2^x +1

v-u = 3^x-2^x

hence v-u != 2(3^x-2^x) hence sufficient

2) x= 3

does not help