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

It is currently 01 Aug 2015, 00:37
GMAT Club Tests

Close

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
Your Progress

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

Not interested in getting valuable practice questions and articles delivered to your email? No problem, unsubscribe here.

Events & Promotions

Events & Promotions in June
Open Detailed Calendar

GMAT Prep DS

  Question banks Downloads My Bookmarks Reviews Important topics  
Author Message
Intern
Intern
avatar
Joined: 18 Apr 2006
Posts: 37
Followers: 0

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

GMAT Prep DS [#permalink] New post 07 Aug 2006, 00:21
00:00
A
B
C
D
E

Difficulty:

(N/A)

Question Stats:

0% (00:00) correct 0% (00:00) wrong based on 0 sessions
This topic is locked. If you want to discuss this question please re-post it in the respective forum.

Explain
Attachments

untitled.JPG
untitled.JPG [ 57.62 KiB | Viewed 481 times ]

SVP
SVP
avatar
Joined: 30 Mar 2006
Posts: 1737
Followers: 1

Kudos [?]: 46 [0], given: 0

 [#permalink] New post 07 Aug 2006, 02:21
B

sqr(x2) = -x when x<0
sqr(x2) = x when x>0

Hence we have to prove that x-3 is negative. this can be true when x is less than 3.

1) x!= 3. X can be less than 3 also greater than 3.
Not suff

2) -x|x| > 0
This can be true only when x < 0

Hence x-3 is <0 Hence sqr{(x-3)^2} = -(x-3) = 3-x
Intern
Intern
avatar
Joined: 26 Apr 2006
Posts: 45
Followers: 0

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

 [#permalink] New post 07 Aug 2006, 09:13
I have a doubt here..
Stmt 2 )
for x< 0 lets say -2

then sqrt(-2-3)^2) != 3- -2

because sqrt(25) != 5
because it can be + 5 or -5.
Please let me know what u think . where am i going wrong ?
SVP
SVP
avatar
Joined: 30 Mar 2006
Posts: 1737
Followers: 1

Kudos [?]: 46 [0], given: 0

 [#permalink] New post 07 Aug 2006, 19:53
techieGuy wrote:
I have a doubt here..
Stmt 2 )
for x< 0 lets say -2

then sqrt(-2-3)^2) != 3- -2

because sqrt(25) != 5
because it can be + 5 or -5.
Please let me know what u think . where am i going wrong ?


It cannot be +5. Put +5 in place of x and you will get a different answer.
Manager
Manager
avatar
Joined: 26 Jun 2006
Posts: 152
Followers: 1

Kudos [?]: 1 [0], given: 0

 [#permalink] New post 07 Aug 2006, 20:04
Agree with (B)


The function sqtr(x) is defined for non-negative X's can take non-negative values...

sqrt(25) = 5 (can not be -5)

similar, sqrt((-5)^2) = 5 (can not be -5)
Manager
Manager
avatar
Joined: 20 Mar 2006
Posts: 200
Followers: 1

Kudos [?]: 1 [0], given: 0

 [#permalink] New post 11 Aug 2006, 19:40
sqrt((x-3)^2) = |x-3|
|x-3| = x-3 for x>=3
|x-3| = 3-x for x< 3

(1) x!= 3
x could be < 3 or >=3 Insuff
BCE
(2) -x|x| > 0
|x| is always +ve
Hence -x>0
i.e x<0
Hence |x-3| = 3-x

Suff
Hence
B
Heman
  [#permalink] 11 Aug 2006, 19:40
Display posts from previous: Sort by

GMAT Prep DS

  Question banks Downloads My Bookmarks Reviews Important topics  


cron

GMAT Club MBA Forum Home| About| Privacy Policy| Terms and Conditions| GMAT Club Rules| Contact| Sitemap

Powered by phpBB © phpBB Group and phpBB SEO

Kindly note that the GMAT® test is a registered trademark of the Graduate Management Admission Council®, and this site has neither been reviewed nor endorsed by GMAC®.