1 DS 8

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1 DS 8

by gmater29 » Fri Oct 23, 2009 4:50 am
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
Last edited by gmater29 on Fri Oct 23, 2009 5:25 am, edited 1 time in total.
Source: — Data Sufficiency |

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Re: 1 DS 8

by uttam.albela » Fri Oct 23, 2009 5:06 am
gmater29 wrote:For all integers n, the function f is defined by f (n) = an, where a is a constant. What is the value of f (1)?
(1) f(2)=100
(2) f(3)=-1,000

f(n)= a ^ n
so f(1) = a ^ 1 = a

So the question is actually what is the value of a?
option 1)
f(2) = a ^ 2 = 100
a = + - 10 , so we do not know a.

option 2)

f(3) = a ^ 3 = -1000
a = -10

so option B alone can give the answer but not A.

So the answer is B :)
Last edited by uttam.albela on Fri Oct 23, 2009 5:35 am, edited 1 time in total.

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by gmater29 » Fri Oct 23, 2009 5:27 am
Apologise, a mistake in the question its f(n) = a^n where a is a constant.

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by uttam.albela » Fri Oct 23, 2009 5:42 am
gmater29 wrote:Apologise, a mistake in the question its f(n) = a^n where a is a constant.
edited the answer. :)