Find all School-related info fast with the new School-Specific MBA Forum

 It is currently 04 May 2015, 16:28

GMAT Club Daily Prep

Thank you for using the timer - this advanced tool can estimate your performance and suggest more practice questions. We have subscribed you to Daily Prep Questions via email.

Customized
for You

we will pick new questions that match your level based on your Timer History

Track

every week, we’ll send you an estimated GMAT score based on your performance

Practice
Pays

we will pick new questions that match your level based on your Timer History

Events & Promotions

Events & Promotions in June
Open Detailed Calendar

Is X^2=?X?? (1)X^2+X>0 (2)X<1, My

Author Message
TAGS:
Intern
Joined: 27 Jul 2007
Posts: 8
Followers: 0

Kudos [?]: 0 [0], given: 0

Is X^2=?X?? (1)X^2+X>0 (2)X<1, My [#permalink]  15 Dec 2007, 21:21
00:00

Difficulty:

(N/A)

Question Stats:

0% (00:00) correct 0% (00:00) wrong based on 0 sessions
Is X^2＝￨X￨?

(1)X^2+X>0

(2)X<1,

first, X^2＝￨X￨ can be reformed ￨X￨^2＝￨X￨
￨X￨^2-￨X￨＝0
￨X￨(￨X￨-1)＝0, X=0, +1, -1

(1)
X(X+1)>0
X<-1 , 0<X
, when X=-1 No, X=0 No, X=1 Yes
so, A can not be possible

(2) X<1,
, when X=-1 Yes, X=0 yes, X=1 No
so, B can not be possible

(1)+(2) is,
X<-1 , 0<X<1
, when X=-1 No, X=0 No, X=1 No

I think the answer is C(coz, this is Data sufficiency Question, No can be answer)

However, some say it is E

I am not confident with my answer,

Am I terribly wrong?

P.S: I am so sorry to make you confused, I rewrited, check this again PLS.

Last edited by leokkim on 16 Dec 2007, 02:24, edited 4 times in total.
CEO
Joined: 17 Nov 2007
Posts: 3578
Concentration: Entrepreneurship, Other
Schools: Chicago (Booth) - Class of 2011
GMAT 1: 750 Q50 V40
Followers: 407

Kudos [?]: 2143 [0], given: 359

Expert's post
C

Is X^2＝￨X| at X e {-1,0,+1}

(1)X^2+X>0 ==> X e (-∞,-1)&(0,+∞). includes {1}. INSUFF.

(2)X<1 ==> X e (-∞,1). includes {-1,0} INSUFF.

(1)&(2) ==> X e (-∞,-1)&(0,1). does not include numbers of set {-1,0,+1} SUFF.
Similar topics Replies Last post
Similar
Topics:
|x+1| + |x+2| + | x-1|= 20 3 30 Jul 2013, 20:26
2 Is x>3 ? 1. (x-1)(x-2)(x-3)>0 2. x>1 12 16 Oct 2011, 16:14
Is x>0? 1) x^2+x-2>0 2) x^3<x^2 (A) Statement 1 7 25 Jan 2008, 15:44
If (-1)*X=1,which of the following is an integer? 1)X/(2+X) 4 24 Jan 2006, 23:34
If the sequence X(1), X(2), X(3),...,X(n),..is such that 5 08 Oct 2005, 03:18
Display posts from previous: Sort by