Function f(n)

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Function f(n)

by money9111 » Wed Feb 03, 2010 11:01 pm
For all integers n, the function f is defined by f(n)=a^n, where a is a constant. What is the value of f(1)?

(1) f(2) = 100
(2) f(3) = -1,000

Data Sufficiency Answer Choices
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Source: — Data Sufficiency |

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by money9111 » Wed Feb 03, 2010 11:02 pm
OA B
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by thephoenix » Wed Feb 03, 2010 11:10 pm
money9111 wrote:For all integers n, the function f is defined by f(n)=a^n, where a is a constant. What is the value of f(1)?

(1) f(2) = 100------a^2=100---->+a=10---->a=+-10 insuff(sqr rut may change the sign of variable)
(2) f(3) = -1,000---->a^3=-1000--->a=-10 ...suff( cube root signs doesn't changes)

hence b

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by papgust » Wed Feb 03, 2010 11:20 pm
Moved to "Data Sufficiency" section!

Please post the questions in the right folder. Thanks!

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by sanju09 » Thu Feb 04, 2010 1:14 am
money9111 wrote:For all integers n, the function f is defined by f(n)=a^n, where a is a constant. What is the value of f(1)?

(1) f(2) = 100
(2) f(3) = -1,000

Data Sufficiency Answer Choices
(1) is insufficient as it gives two values for a, which would, in turn, give two answers for f (1).

(2) is sufficient as it directly solves down to a = -10. Now, when a is fixed, problem is fixed.


[spoiler]B[/spoiler]
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by money9111 » Thu Feb 04, 2010 8:21 am
YIKES! papgust ... i apologize..
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