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If f(x) = x^x,then f(f(x)) = [#permalink]
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23 Jun 2014, 01:51
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If \(f(x)= x^x,\) then \(f(f(x))=\) Attachment:
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Got this Question in Veritas prep test . Can this question be done by plugging in some values..
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If f(x) = x^x,then f(f(x)) = [#permalink]
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23 Jun 2014, 02:25
\(f(x) = x^x\) \(f[f(x)] = f(x)^{f(x)}\) \(= (x^x)^{(x^x)}\) \(= x^{(x*x^x)}\) \(= x^{x^{1+x}}\) = Answer = D
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Re: If f(x) = x^x,then f(f(x)) = [#permalink]
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23 Jun 2014, 03:37
PareshGmat wrote: \(f(x) = x^x\)
\(f[f(x)] = f(x)^{f(x)}\)
\(= (x^x)^{(x^x)}\)
\(= x^{(x. x^x)}\)
\(= x^{x^{1+x}}\)
= Answer = D Thanks for your reply Would you try this question by plugging in. The question looked good for plugging in options but I am not getting the answer.
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If f(x) = x^x,then f(f(x)) = [#permalink]
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Updated on: 25 Sep 2014, 18:40
WoundedTiger wrote: PareshGmat wrote: \(f(x) = x^x\)
\(f[f(x)] = f(x)^{f(x)}\)
\(= (x^x)^{(x^x)}\)
\(= x^{(x. x^x)}\)
\(= x^{x^{1+x}}\)
= Answer = D Thanks for your reply Would you try this question by plugging in. The question looked good for plugging in options but I am not getting the answer. From the derived answer: \(f(3) = 3^{3^{(1+3)}}\) \(= 3^{(3^4)}\) \(= 3^{81}\)........... (1) \(f[f(3)] = (3^3)^{(3^3)}\) \(= (3^3)^{27}\) \(= 3^{(27*3)}\) \(= 3^{81}\) ............ (2) (1) = (2)
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Originally posted by PareshGmat on 23 Jun 2014, 03:55.
Last edited by PareshGmat on 25 Sep 2014, 18:40, edited 1 time in total.



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If f(x) = x^x,then f(f(x)) = [#permalink]
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23 Jun 2014, 04:07
Please note: \(2^{3^2} = 2^{(3^2)} = 2^9 = 512\) \((2^3)^2 = 2^{(3*2)} = 2^6 = 64\) OR \((2^3)^2 = 8^2 = 64\) Power calculations go from top to bottom, if brackets are not provided
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Re: If f(x) = x^x,then f(f(x)) = [#permalink]
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23 Jun 2014, 05:49



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Re: If f(x) = x^x,then f(f(x)) = [#permalink]
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07 Oct 2017, 08:07
Bunuel wrote: WoundedTiger wrote: If \(f(x)= x^x,\) then \(f(f(x))=\) Attachment: Untitled.png Got this Question in Veritas prep test . Can this question be done by plugging in some values.. Added this question to functions directory in Special Questions DirectoryOperations/functions defining algebraic/arithmetic expressionsSymbols Representing Arithmetic OperationRounding FunctionsVarious Functionshi Bunuel the use of exponents is little bit trickier to me here please let me understand... f [ f(x) ] to the power f(x) that is [ f (x) ] is raised to power f(x).. NOT, f (x) is raised to power f(x), if this is so, then it may mean, in f(x), "x" is raised to the power f(x), and thus may end up with result looking like option A So, the expression here is meant to be "[ f (x) ]" (the whole) is raised to the power f(x)" and thus option D is right Am I right or wrong ....? please help me get rid of my doubts ... thanks in advance, man



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Re: If f(x) = x^x,then f(f(x)) = [#permalink]
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07 Oct 2017, 08:20
gmatcracker2017 wrote: Bunuel wrote: WoundedTiger wrote: If \(f(x)= x^x,\) then \(f(f(x))=\) Attachment: Untitled.png Got this Question in Veritas prep test . Can this question be done by plugging in some values.. Added this question to functions directory in Special Questions DirectoryOperations/functions defining algebraic/arithmetic expressionsSymbols Representing Arithmetic OperationRounding FunctionsVarious Functionshi Bunuel the use of exponents is little bit trickier to me here please let me understand... f [ f(x) ] to the power f(x) that is [ f (x) ] is raised to power f(x).. NOT, f (x) is raised to power f(x), if this is so, then it may mean, in f(x), "x" is raised to the power f(x), and thus may end up with result looking like option A So, the expression here is meant to be "[ f (x) ]" (the whole) is raised to the power f(x)" and thus option D is right Am I right or wrong ....? please help me get rid of my doubts ... thanks in advance, man Paresh HERE explains it so perfectly that I have nothing to add.
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