Set 25 Q: 34 - Mod

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Set 25 Q: 34 - Mod

by kv_ajay » Sun Sep 21, 2008 10:29 pm
If M+4 =2, what is the value of M?
(1) M<0 (2) M^2+8M+12=0

I answered D...

OA is [spoiler]E[/spoiler]

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by mals24 » Mon Sep 22, 2008 3:55 am
I agree the answer should be D

The ques says m+4=2
m=2 or m=-2 depending on whether m is positive or negative.

St 1 says m<0 So m=-2---SUFF

St 2 says m2+8m+12=0
m=-6, m=-2
m=-2---SUFF

Answer is D

Unless I'm missing something???

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by Sachindh » Mon Sep 22, 2008 9:57 pm
I could not understand the question clearly.
if M+4=2 then isn't it clear that M=-2. So, why do we need any other statement when answer is deducible from question itself.

Is the question typed correctly?

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by mals24 » Tue Sep 23, 2008 3:37 am
Ok i just checked and the question posted is incorrect

The original question had a mod in the ques and the orginal equation read mod(m+4)=2

So in this case the answer is E

So the equation could either be -(m+4)=2; -m-4=2; m=-6
(m+4)=2, m=-2

St 1: M<0
Still unclear if m=-6 or -2

St 2
m^2+8m+12=0
again we have two values for m=-6 or -2

Combining 1 & 2 we still dont get a clear soln for m

Hence the answer is E

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by kv_ajay » Wed Sep 24, 2008 8:27 pm
My bad...i did not post it correctly..

But i agree that answer is E