here i got E
just now nothing more that plugging numbers
(1) m>n
m=2,n=1
|2-1|=1, |2|-|1|=2-1=1. yes
m=2, n=-1
|2+1|=3, |2|-|-1|=2-1=1. no
so 1 st insufficient
(2) m+n>0
m=2, n=1 yes
m=2, n=-1, no
again insufficient
from both m>0, but we uncertain about sign of n
so E
DS I have a doubt
This topic has expert replies
Source: Beat The GMAT — Data Sufficiency |
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outreach
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|m-n|=|m|-|n|
Squaring both the sides
m^2-2mn+n^2=m^2-2|m||n|+n^2
mn=|m||n| is the Q
1)
m>n
m=-2,n=-3 Q satisfied
m=2,n=-1 Q not satisfied
insuff
2)
m> -n
m=2,n=-1 Q not satisfied
m=2,n=1 Q satisfied
insuff
combined 1 and 2
insuff
E
Squaring both the sides
m^2-2mn+n^2=m^2-2|m||n|+n^2
mn=|m||n| is the Q
1)
m>n
m=-2,n=-3 Q satisfied
m=2,n=-1 Q not satisfied
insuff
2)
m> -n
m=2,n=-1 Q not satisfied
m=2,n=1 Q satisfied
insuff
combined 1 and 2
insuff
E
Raffy wrote:|m-n|=|m|-|n|
1) m-n>0
2)m+n>0
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clock60
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hi outreach
honestly speaking i start to solve this problem like you did, but i began to hesitate about squaring
|m|-|n|-?
my question: is it always valid to square here as |m|-|n| can result in -ve number.
honestly speaking i start to solve this problem like you did, but i began to hesitate about squaring
|m|-|n|-?
my question: is it always valid to square here as |m|-|n| can result in -ve number.
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aloneontheedge
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Outreach,outreach wrote:|m-n|=|m|-|n|
Squaring both the sides
m^2-2mn+n^2=m^2-2|m||n|+n^2
mn=|m||n| is the Q
1)
m>n
m=-2,n=-3 Q satisfied
m=2,n=-1 Q not satisfied
insuff
2)
m> -n
m=2,n=-1 Q not satisfied
m=2,n=1 Q satisfied
insuff
combined 1 and 2
insuff
E
Raffy wrote:|m-n|=|m|-|n|
1) m-n>0
2)m+n>0
the question isnt clear,how did you start answering?
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indiantiger
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Can we solve inequality equations as :
m - n> 0
+m + n>0
-------------------
2m > 0
giving = m >0
m - n> 0
+m + n>0
-------------------
2m > 0
giving = m >0
"Single Malt is better than Blended"
