GMAT Prep - Modulus & Square Roots

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GMAT Prep - Modulus & Square Roots

by aditikedia » Fri Aug 08, 2008 6:12 am
Again, not sure how this can be done..

Please help..
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Re: GMAT Prep - Modulus & Square Roots

by olika » Fri Aug 08, 2008 6:28 am
Is the ans. E?

root (5) is greater than root (2), so substract and you result in negative number which is not the real number.

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by aditikedia » Fri Aug 08, 2008 6:58 am
Yes it is the answer. However, not sure whether it's ok to stop the moment you get square root of a negative number.

A detailed explanation would really help here..

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by santa_dem » Fri Aug 08, 2008 7:04 am
aditikedia wrote:Yes it is the answer. However, not sure whether it's ok to stop the moment you get square root of a negative number.

A detailed explanation would really help here..
Actualy, it's ok to stop, 'cause root of a negative is not a real number, therefore the whole expresion is not a real number.

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by bourne159 » Fri Aug 08, 2008 1:46 pm
Answer is E.

The square root of a negative number is not a real number.
In GMAT I think you should stop as soon as you see a square root of a negative number since GMAT does not deal with imaginary numbers etc...

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by aditikedia » Fri Aug 08, 2008 5:49 pm
Thanks everyone! :)

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by smclean23 » Sun Aug 10, 2008 7:30 pm
Could someone explain the step by step process?

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by sudhir3127 » Sun Aug 10, 2008 8:07 pm
IF you solve only sqroot(2- sqroot x) part it is enough

take X to be 5. which is 2.23
sqroot ( 2- sqroot 5)

sqroot ( 2- 2.23)
sqrt( -0.23)

As sq root of a negative number is non real. the answer shud be 5.

hope it helps..