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#1 2007-03-26 09:12:45

kai89
Member
Registered: 2007-03-26
Posts: 1

discrete math induction proof

Could someone...anyone help me with this proof?

Prove that n!+k is divisible by k, for all integers n is less than or equal to 2 and k=2,3,...n.
any help is greatly appreciated thanks

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#2 2007-03-26 09:29:16

pi man
Member
Registered: 2006-07-06
Posts: 251

Re: discrete math induction proof

Did you mean "n is GREATER than or equal to 2"?

This is not a "proof" and this is not a strong area for me, but....

So we just need to show that n! is divisble by k....
n! = 1 * 2 * 3 * ... * k * .... * n-1 * n   Since k is a factor of n!, n! must be divisble by k.

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#3 2007-03-26 10:31:52

kai89
Member
Registered: 2007-03-26
Posts: 1

Re: discrete math induction proof

yes i did... n is greater than or equal to 2

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#4 2007-03-27 02:30:26

Stanley_Marsh
Member
Registered: 2006-12-13
Posts: 345

Re: discrete math induction proof

Actually, u imply that k is smaller than n , then n! must contains one k , then  k | n! ,  therefore k | n!+k


Numbers are the essence of the Universe

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