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Source: — Data Sufficiency |

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by gmataug08 » Tue Dec 02, 2008 11:22 am
if number and its reciprocal on subraction gives 0, then that implies that the number is equal to its reciprocal.
only 1 satisfies this condition.

we have two choices, any integer to the power of 0 gives 1
or else 1 to the power of any value.

stmt 1) x is integer no information on n , hence X could be 0 or 1
INSUFF

stmt 2) n!= 0 , implies x has to be 1 , but it can be -1 or +1.
INSUFF

hence E

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by cramya » Tue Dec 02, 2008 3:35 pm
x^n = 1/x^n

Stmt I

x could be 1,2,3,4 etc... if n=0
x could be -1 if n is 1

Many possibilities

INSUFF

Stmt II
n is not 0

x could be 1 or -1

INSUFF

Stmt I and II

-1 and 1 atre both intgers and n could be 1

INSUFF

E)

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by jimmiejaz » Wed Dec 03, 2008 5:05 am
we can rearrange the eqn as x^2n=1
from 1 we have x is an integer
we can have x as any integer as long as n=0 or x=-1 or 1 and n can take any value. hence insuff.

from 2 we have n is not equal to 0. still x can be -1 or 1.
hence insuf.
combining
we have x can be -1 or 1

hence E.
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