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a = 2 - (1/a)

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a = 2 - (1/a)

by sanju09 » Fri Feb 05, 2010 6:25 am
If a = 2 - (1/a), what is the value of integer n?

(1) a = 2^n.

(2) a^n = 1/(a^n).
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by ajith » Fri Feb 05, 2010 6:46 am
sanju09 wrote:If a = 2 - (1/a), what is the value of integer n?

(1) a = 2^n.

(2) a^n = 1/(a^n).

a^2 = 2a -1
a^2 -2a +1
(a-1)^2=0
a=1
[assumption a is not zero)

1) a= 2^n

n=0 Sufficient

2) since a= 1
a^n = 1/(a^n) for all values of n; insufficient

A
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