sqaure root of 4

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sqaure root of 4

by agarwalva » Sun May 13, 2012 2:04 pm
I have a stupid q/s ..

In Manhattan guide says

1. if √4 = x, then x =2

2. if x^2 = 4 then x= 2 or x= -2

I never understood point 1.. I always knew point 2
Please can someone explain
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by neelgandham » Sun May 13, 2012 3:06 pm
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by aneesh.kg » Sun May 13, 2012 9:05 pm
Hi agarwalva,

That's a very good doubt.

You can read my post here:
https://www.beatthegmat.com/inequalities-t111308.html
and get it clarified.
Aneesh Bangia
GMAT Math Coach
[email protected]

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by amit28it » Sun May 13, 2012 11:02 pm
Hey agarwalva,
Look, √4 shows the square root of 4 and as you know that square root of a number is that value which when multiplied by itself, gives the number.For example-
√36 = 6 (as 6 x 6 = 36)
same with √4 = 2 (2 x 2 = 4)
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by hey_thr67 » Mon May 14, 2012 1:05 am
Hi,

I am not able to grasp this idea. Can somebody please explain it more or post questions which use this concept . @agarwalva could you please tell which guide you are using ?

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by Bill@VeritasPrep » Mon May 14, 2012 11:32 am
When the radical is used, we are only concerned with the principal (positive) square root. If we have a squared variable, then we need both positive and negative roots.
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