the value of p?

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the value of p?

by sanju09 » Tue Aug 28, 2012 1:52 am
If p is an integer, what is the value of p?

(1) (|p|!)^p = |p|!.
(2) p^p = p^2.

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by vk_vinayak » Tue Aug 28, 2012 2:10 am
sanju09 wrote:If p is an integer, what is the value of p?

(1) (|p|!)^p = |p|!.
(2) p^p = p^2.

[spoiler]OA C[/spoiler]

Source: gmatclub
Very good question. I first chose A, thinking that 0 can't be raised to the power of 0. But forgot that 0!=1

1). (|p|!)^p = |p|! => p=0 or p=1. INSUF
2). p^p = p^2 => p=1 or p=2. INSUF

Combining. p=1. SUFFICIENT.

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by neelgandham » Tue Aug 28, 2012 3:03 am
vk_vinayak1 wrote:. (|p|!)^p = |p|! => p=0 or p=1. INSUF
2). p^p = p^2 => p=1 or p=2. INSUF
Some might argue that if p =0, then 0^0 = 0^2 = 0. So, p = 0,1,2 is the solution set. For all those who agree with this, read this awe-CLAP-some article here - https://www.askamathematician.com/2010/1 ... -disagree/
Last edited by neelgandham on Tue Aug 28, 2012 4:12 am, edited 1 time in total.
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by vk_vinayak » Tue Aug 28, 2012 3:57 am
neelgandham wrote:[quote="vk_vinayak1). (|p|!)^p = |p|! => p=0 or p=1. INSUF
2). p^p = p^2 => p=1 or p=2. INSUF
Some might argue that if p =0, then 0^0 = 0^2 = 0. So, p = 0,1,2 is the solution set. For all those who agree with this, read this awe-CLAP-some article here - https://www.askamathematician.com/2010/1 ... -disagree/[/quote]

Thanks, Anil. Does GMAT consider 0^0=1 ? If yes, do you remember any OG problems that shows this.
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by neelgandham » Tue Aug 28, 2012 4:03 am
0^0 = Undefined (GMAT or otherwise) to the best of my knowledge and to answer your question. NO, I haven't seen any such problems.
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