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stolyar
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Is number Z even? (1) Z!=1 (2) |Z|!=Z 14 Jun 2004, 12:06
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Is number Z even?

(1) Z!=1

(2) |Z|!=Z



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Makky07
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Is number Z even? (1) Z!=1 (2) |Z|!=Z 14 Jun 2004, 12:50
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Yep, C it is.

With statement 1, Z could be 0 or 1

With statement 2, Z could be 2 or 1

Z = 1 and 1 is odd.
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TIANMU
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Is number Z even? (1) Z!=1 (2) |Z|!=Z 17 Jun 2004, 16:15
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I don't really understand why 0!=1?
I understand 3! will be 3×2×1=6, but I don't know
how to calculate 0! Please let me know. Thank you.
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Emmanuel
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Is number Z even? (1) Z!=1 (2) |Z|!=Z 18 Jun 2004, 01:53
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TIANMU
I don't really understand why 0!=1?
I understand 3! will be 3×2×1=6, but I don't know
how to calculate 0! Please let me know. Thank you.
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Don't worry, 0! = 1 BY DEFINITION. Had you known definition of gamma-function, you would have come with such property: gamma(n) = (n-1)!, gamma(1) = 1. => 0! = 1.

how is gamma function defined? It is equal to (see picture):
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mba
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Is number Z even? (1) Z!=1 (2) |Z|!=Z 18 Jun 2004, 07:34
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I believe (B) should be the answer, because |Z|! will be Z only when Z is -1 or 1. Hence Z is ODD. Any explanations??
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Is number Z even? (1) Z!=1 (2) |Z|!=Z 18 Jun 2004, 07:56
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mba
I believe (B) should be the answer, because |Z|! will be Z only when Z is -1 or 1. Hence Z is ODD. Any explanations??
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-1 does not satisfy the second equation, for any factorial is always POSITIVE.
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Is number Z even? (1) Z!=1 (2) |Z|!=Z 18 Jun 2004, 08:35
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Emmanuel
TIANMU
I don't really understand why 0!=1?
I understand 3! will be 3×2×1=6, but I don't know
how to calculate 0! Please let me know. Thank you.

Don't worry, 0! = 1 BY DEFINITION. Had you known definition of gamma-function, you would have come with such property: gamma(n) = (n-1)!, gamma(1) = 1. => 0! = 1.

how is gamma function defined? It is equal to (see picture):
Show more


Thank you very much, Emmanuel !
I didn't know this definition, but I learn it now.



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Hi there,
This topic has been closed and archived due to inactivity or violation of community quality standards. No more replies are possible here.
Where to now? Join ongoing discussions on thousands of quality questions in our Data Sufficiency (DS) Forum
Still interested in this question? Check out the "Best Topics" block above for a better discussion on this exact question, as well as several more related questions.
Thank you for understanding, and happy exploring!
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