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

It is currently 04 Aug 2015, 02:53
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

If # denotes a mathematical operation, does x#y=y#x for all

  Question banks Downloads My Bookmarks Reviews Important topics  
Author Message
VP
VP
avatar
Joined: 21 Mar 2006
Posts: 1135
Location: Bangalore
Followers: 2

Kudos [?]: 30 [0], given: 0

If # denotes a mathematical operation, does x#y=y#x for all [#permalink] New post 14 Nov 2006, 17:14
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.

If # denotes a mathematical operation, does
x#y=y#x for all x and y?
(1) For all x and y, x#y = 2(x2 + y2).
(2) For all y, 0#y = 2 y2

I got the answer right, but I took a really long time. Can anyone please explain the science behind this?
Senior Manager
Senior Manager
User avatar
Joined: 01 Sep 2006
Posts: 301
Location: Phoenix, AZ, USA
Followers: 1

Kudos [?]: 15 [0], given: 0

[#permalink] New post 14 Nov 2006, 17:23
If # denotes a mathematical operation, does
x#y=y#x for all x and y?
(1) For all x and y, x#y = 2(x2 + y2).
(2) For all y, 0#y = 2 y2


using (1)

2#3= 2( 2^2 + 3^2)

-2#3 = 2 ( (-2)^2 + 3^2)

since x and y are being squared sign doent matter

i will conclue x#y = y#x

suff

using (2)

0#y = 2 y^2

This could mean x#y = 2( x^2 + y^2)

it could also mean 2 ( x + y^2) for 0#y this would give same result as (2)

insuff
A   [#permalink] 14 Nov 2006, 17:23
Display posts from previous: Sort by

If # denotes a mathematical operation, does x#y=y#x for all

  Question banks Downloads My Bookmarks Reviews Important topics  


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®.