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#1 2006-12-28 01:22:19

balasvce
Member
Registered: 2006-12-20
Posts: 37

can yu make this question complete . justify!

1.n=s^2t; n is a multiple of 7 and which is multiple of 49

options were

s^2t

s^2

t and some thing like...i hope answer is s^t

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#2 2006-12-28 08:12:26

krassi_holmz
Real Member
Registered: 2005-12-02
Posts: 1,905

Re: can yu make this question complete . justify!

Nope. We're sure only for 7/s^t.
So 7^2/(s^t)^2 = s^2t, option 1


IPBLE:  Increasing Performance By Lowering Expectations.

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#3 2006-12-29 03:08:57

er.neerajsrivastava
Member
Registered: 2006-12-27
Posts: 9

Re: can yu make this question complete . justify!

how can it be sure as s^2t itself is multiple of 7, i think atleast it should be s^4t.

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#4 2006-12-29 06:36:28

krassi_holmz
Real Member
Registered: 2005-12-02
Posts: 1,905

Re: can yu make this question complete . justify!

er.neerajsrivastava wrote:

how can it be sure as s^2t itself is multiple of 7, i think atleast it should be s^4t.


So s^2t is a square:
s^2t=a*a (a=s^t)
AND...
7 is prime number.
Knowing that if a prime number divides a square of x, then it also divides x, we get:
7/s^t, so 7^2/s^2t


IPBLE:  Increasing Performance By Lowering Expectations.

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#5 2006-12-29 06:46:00

Ricky
Moderator
Registered: 2005-12-04
Posts: 3,791

Re: can yu make this question complete . justify!

Knowing that if a prime number divides a square of x, then it also divides x

Or in more general terms:



"In the real world, this would be a problem.  But in mathematics, we can just define a place where this problem doesn't exist.  So we'll go ahead and do that now..."

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#6 2006-12-29 06:52:15

krassi_holmz
Real Member
Registered: 2005-12-02
Posts: 1,905

Re: can yu make this question complete . justify!

Or more general:

Last edited by krassi_holmz (2006-12-29 06:52:51)


IPBLE:  Increasing Performance By Lowering Expectations.

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#7 2006-12-29 15:34:14

Ricky
Moderator
Registered: 2005-12-04
Posts: 3,791

Re: can yu make this question complete . justify!

Or more general:



"In the real world, this would be a problem.  But in mathematics, we can just define a place where this problem doesn't exist.  So we'll go ahead and do that now..."

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#8 2006-12-30 03:51:12

krassi_holmz
Real Member
Registered: 2005-12-02
Posts: 1,905

Re: can yu make this question complete . justify!

Or more general:

Last edited by krassi_holmz (2006-12-30 03:52:09)


IPBLE:  Increasing Performance By Lowering Expectations.

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