1000 DS section 5- Q-23

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1000 DS section 5- Q-23

by ash_maverick » Thu Jun 11, 2009 9:14 am
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

Can somebody please provide me the step wise solution?
Source: — Data Sufficiency |

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by abhinav85 » Thu Jun 11, 2009 10:55 am
IMO D

the sign between x and y denotes addition.

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by tohellandback » Thu Jun 11, 2009 6:52 pm
IMO A
1)x☉y = 2(x2 + y2).
so, y☉x = 2( y2+x2 ).
both are same ..SUFF

2) nothing is being said about x-INSUFF
The powers of two are bloody impolite!!

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by bizwizashish » Sat Jun 13, 2009 8:59 am
does the original question says mathmetical operation or function....

If operation.. i don't think we can find anything.. but if it's function then answer is D
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Ashish Khandelwal

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by rahulg83 » Sun Jun 14, 2009 2:11 am
IMO A

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by Vemuri » Sun Jun 14, 2009 2:49 am
IMO A. I agree with tohellandback's explanation

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by Naruto » Sun Jun 14, 2009 5:37 am
IMO A , Ditto as To hellandback. Whats the OA. Hey guys i wanted to know if 1000 series are any useful?

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by tohellandback » Sun Jun 14, 2009 5:41 am
Naruto wrote:IMO A , Ditto as To hellandback. Whats the OA. Hey guys i wanted to know if 1000 series are any useful?
I have been told that the 1000 series has got a errors in the answers
The powers of two are bloody impolite!!

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Re: 1000 DS section 5- Q-23

by mna123 » Sun Jun 14, 2009 7:44 am
ash_maverick wrote: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

Can somebody please provide me the step wise solution?

Can you please send me 1000 DS at namon20ATyahoodotcom