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by vaivish » Tue Aug 26, 2008 8:04 am
82. If k^(xy)=1, where k is not zero, which of the following must be true?
I. k=1
II. x=0
III. y=0
(A) I only
(B) II only
(C) III only
(D) I and II
(E) None


Oa is e.
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Re: 82

by sudhir3127 » Tue Aug 26, 2008 8:22 am
vaivish wrote:82. If k^(xy)=1, where k is not zero, which of the following must be true?
I. k=1
II. x=0
III. y=0
(A) I only
(B) II only
(C) III only
(D) I and II
(E) None


Oa is e.
just knowledge of one information can help u immensely while u solve this

n^0 = 1 ( where is n non zero)

k^xy =1 where k #0

means either X has to be zero or Y has to be zero or both zero.

none of the options mentions that.

hence E.

hope that helps..
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Re: 82

by mehravikas » Tue Aug 26, 2008 8:10 pm
But k could be 1 and both x and y also 1.

In that case also, k^xy = 1.
sudhir3127 wrote:
vaivish wrote:82. If k^(xy)=1, where k is not zero, which of the following must be true?
I. k=1
II. x=0
III. y=0
(A) I only
(B) II only
(C) III only
(D) I and II
(E) None


Oa is e.
just knowledge of one information can help u immensely while u solve this

n^0 = 1 ( where is n non zero)

k^xy =1 where k #0

means either X has to be zero or Y has to be zero or both zero.

none of the options mentions that.

hence E.

hope that helps..
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Re: 82

by sudhir3127 » Tue Aug 26, 2008 8:20 pm
mehravikas wrote:But k could be 1 and both x and y also 1.

In that case also, k^xy = 1.
sudhir3127 wrote:
vaivish wrote:82. If k^(xy)=1, where k is not zero, which of the following must be true?
I. k=1
II. x=0
III. y=0
(A) I only
(B) II only
(C) III only
(D) I and II
(E) None


Oa is e.
just knowledge of one information can help u immensely while u solve this

n^0 = 1 ( where is n non zero)

k^xy =1 where k #0

means either X has to be zero or Y has to be zero or both zero.

none of the options mentions that.

hence E.

hope that helps..
ur right on the logic.. but still we dont have any option with that .... hence E good find...

thanks vikas
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by mehravikas » Wed Aug 27, 2008 10:52 am
I understand your point, the k = x = y = 1 condition could be true but its not must be true.

Thanks again.
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by Thouraya » Wed Jun 02, 2010 1:52 am
Its one of three options:

1) K=1, and x and y any number
2)K any number and either x or y =0
3)K any number and both x and y 0

SO the right solution is E cuz either one of the above options must be right not more, true?
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