is 0^0 defined in GMAT??!!

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Source: — Data Sufficiency |

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by alex.gellatly » Mon Aug 06, 2012 11:36 pm
mehaksal wrote:What is the value of integer j ?

1. |J| = J^-1
2. J^J=1
I get A and here's why:

Statement 1: |J| = J^-1
J^-1 is just 1/J The only way|J| = 1/J is if J is in fact 1. Then |1| = 1/1 or 1 = 1
Sufficient

Statement 2: J^J= 1
Here J could be either 1 or 0. Remember n^0=1 for any number n (including 0 itself)

Does this help?
A useful website I found that has every quant OG video explanation:

https://www.beatthegmat.com/useful-websi ... tml#475231

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by Anurag@Gurome » Mon Aug 06, 2012 11:39 pm
mehaksal wrote:What is the value of integer j ?

1. |J| = J^-1
2. J^J=1
(1) |J| = J^-1 implies |J| = 1/J
Now |J| will always be positive.
|J| = 1/J implies J² = 1. So, J = 1 or -1. But J has to be positive always. So, J = 1; SUFFICIENT.

(2) J^J = 1
If J = 0, then 0^0 = 1
If J = 1, then 1^1 = 1
No definite answer; NOT sufficient.

The correct answer is A.
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by Brent@GMATPrepNow » Tue Aug 07, 2012 7:02 am
The issue of the value of 0^0 has been discussed many times on this site.
Here's one such example: https://www.beatthegmat.com/zero-raised- ... 69042.html

When you check the official guide, you'll see that the test-makers don't address the issue. When they discuss powers of zero, they restrict the conversation to positive bases and say that x^0 = 1 when x>0. Of course, I'm pretty sure that they would concede that x^0 = 1 when x<0.

However, since the test-maker makes no attempt to discuss the value of 0^0, I'm quite sure that you'd never find an official GMAT question that hinges on this.

Cheers,
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by mehaksal » Wed Aug 08, 2012 10:43 pm
thanku :)