Values

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Values

by jayanti » Wed Aug 10, 2011 10:52 pm
Q) For positive integers k , the function g is defined by g(k) = C^k+ 2, where C is a constant.What is the value of g(2)?

(1) g(4) = 18
(2) g(5) = -30

Correct answer is D
Source: — Data Sufficiency |

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by GmatKiss » Thu Aug 11, 2011 1:28 am
Is it g(k) = (C^k)+ 2 or g(k) = C^(k+ 2)?

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by jayanti » Thu Aug 11, 2011 3:33 am
g(k) = (C^k)+ 2

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by Frankenstein » Thu Aug 11, 2011 3:45 am
Hi,
From(1):
c^4 + 2 = 18 =>c^4 = 16.
So, c^2 = 4
g(2) = c^2 + 2 = 6
Sufficient
From(2):
c^5 + 2 = -30 => c^5 = -32
=> c = -2
So, g(2) = c^2 + 2 = (-2)^2 + 2 = 6
Sufficient

Hence, D
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