can u post the OA pls...erukumk wrote:is |X| < 1?
1) |X+1|=2|X-1|
2)|X-3|!=0
Is it C?
is |x| < 1?
Source: Beat The GMAT — Data Sufficiency |
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logitech
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Question can be paraphrased as:erukumk wrote:is |X| < 1?
1) |X+1|=2|X-1|
2)|X-3|!=0
Is X between -1 and + 1 ?
1) |X+1|=2|X-1|
if we take the square of both side and re-arrange it:
3X^2 - 10X + 3 = 0
X = 1/3 or X = 3
INSUF
2) IX-3|!=0
|X-3|!=0 , 0! = 0
Means that X=3
3 is not between -1 and + 1
Sufficient
Hence, B
LGTCH
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bluementor
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Correct me if I'm wrong here:logitech wrote: 2) IX-3|!=0
|X-3|!=0 , 0! = 0
Means that X=3
3 is not between -1 and + 1
Sufficient
Hence, B
|x-3|!=0 simply means x !=3. Therefore, x could lie between -1 and 1 or it could be anything else, except 3. So this statement is not sufficient.
-BM-
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logitech
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|x-3|!=0bluementor wrote:Correct me if I'm wrong here:logitech wrote: 2) IX-3|!=0
|X-3|!=0 , 0! = 0
Means that X=3
3 is not between -1 and + 1
Sufficient
Hence, B
|x-3|!=0 simply means x !=3. Therefore, x could lie between -1 and 1 or it could be anything else, except 3. So this statement is not sufficient.
-BM-
Okay I just checked it and The factorial 0! evaluates to 1.
So this disproves my solution. I don't know what |x-3|!=0 means!
LGTCH
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"DON'T LET ANYONE STEAL YOUR DREAM!"
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"DON'T LET ANYONE STEAL YOUR DREAM!"
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bluementor
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x != 0 means x not equal to 0.logitech wrote:
|x-3|!=0
Okay I just checked it and The factorial 0! evaluates to 1.
So this disproves my solution. I don't know what |x-3|!=0 means!
-BM-
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logitech
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it does not make any sense my friend.bluementor wrote:x != 0 means x not equal to 0.logitech wrote:
|x-3|!=0
Okay I just checked it and The factorial 0! evaluates to 1.
So this disproves my solution. I don't know what |x-3|!=0 means!
-BM-
So what is X ? if not 0 ( we know it is not ZERO )
LGTCH
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"DON'T LET ANYONE STEAL YOUR DREAM!"
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"DON'T LET ANYONE STEAL YOUR DREAM!"
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bluementor
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Well, we don't know what x is. All we know about x is that its not equal to 0. Thats what x != 0 means.logitech wrote:it does not make any sense my friend.bluementor wrote:x != 0 means x not equal to 0.logitech wrote:
|x-3|!=0
Okay I just checked it and The factorial 0! evaluates to 1.
So this disproves my solution. I don't know what |x-3|!=0 means!
-BM-
So what is X ? if not 0 ( we know it is not ZERO )
P.S. By the way, this x!=0 thing has nothing to do with the original problem here. I'm just using this to clearify the meaning of the != notation. You will definitely not see this type of notation being used in the real test, gmatprep or other books. It is only being used here since the proper "not equal to" sign is not easily produced with the keyboard.
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scoobydooby
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|x-3|!=0
or (x-3)(x-2)(x-1)x......1=0 one of these terms must be 0
or x=0 or x=3 or x=2 ..so on. there is no definite value of x
or (x-3)(x-2)(x-1)x......1=0 one of these terms must be 0
or x=0 or x=3 or x=2 ..so on. there is no definite value of x
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Stuart@KaplanGMAT
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Everyone just needs to read statement (2) as:
(2) |x - 3| is not equal to 0
In other words, all (2) tells us is that x is NOT equal to 3. x could be anything else, so (2) is insufficient.
When we combine, we know that:
(1) x = 1/3 or x = 3
(2) x can't be 3
So, together, x = 1/3, which gives us a definite YES answer ... choose (c) together sufficient, apart insufficient.
As bluementor noted, the notation "!=" is often used to stand for "not equal to" and is NOT notation that you'll ever see on the GMAT.
(2) |x - 3| is not equal to 0
In other words, all (2) tells us is that x is NOT equal to 3. x could be anything else, so (2) is insufficient.
When we combine, we know that:
(1) x = 1/3 or x = 3
(2) x can't be 3
So, together, x = 1/3, which gives us a definite YES answer ... choose (c) together sufficient, apart insufficient.
As bluementor noted, the notation "!=" is often used to stand for "not equal to" and is NOT notation that you'll ever see on the GMAT.
Stuart Kovinsky | Kaplan GMAT Faculty | Toronto
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logitech
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Bluementor - thank you!Stuart Kovinsky wrote:Everyone just needs to read statement (2) as:
(2) |x - 3| is not equal to 0
In other words, all (2) tells us is that x is NOT equal to 3. x could be anything else, so (2) is insufficient.
When we combine, we know that:
(1) x = 1/3 or x = 3
(2) x can't be 3
So, together, x = 1/3, which gives us a definite YES answer ... choose (c) together sufficient, apart insufficient.
As bluementor noted, the notation "!=" is often used to stand for "not equal to" and is NOT notation that you'll ever see on the GMAT.
Thanks Stuart for making it clear.
LGTCH
---------------------
"DON'T LET ANYONE STEAL YOUR DREAM!"
---------------------
"DON'T LET ANYONE STEAL YOUR DREAM!"
for statement 1: can you tell me why did you square on both sides??logitech wrote:Question can be paraphrased as:erukumk wrote:is |X| < 1?
1) |X+1|=2|X-1|
2)|X-3|!=0
Is X between -1 and + 1 ?
1) |X+1|=2|X-1|
if we take the square of both side and re-arrange it:
3X^2 - 10X + 3 = 0
X = 1/3 or X = 3
INSUF
2) IX-3|!=0
|X-3|!=0 , 0! = 0
Means that X=3
3 is not between -1 and + 1
Sufficient
Hence, B
