Gmat Prep Absolute and Square root question

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Source: — Data Sufficiency |

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by amitansu » Mon May 26, 2008 10:12 pm
Is ans D here !

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by netigen » Tue May 27, 2008 12:06 am
Ans is B

you can rephrase the term as

is |x-3| = 3-x ?

from (B) we know that x<0 and the equation above is true for all x<0

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by khurram » Tue May 27, 2008 6:17 am
Ans is B Indeed.

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khurram

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by khurram » Tue May 27, 2008 6:21 am
Hello Why do you put absolute value when taking out the square root.

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by gabriel » Tue May 27, 2008 7:02 am
Because value of a sq root is considered to be positive. That is sqroot (4) = 2 and not 2 and -2. This is the general rule unless specified otherwise.

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by khurram » Tue May 27, 2008 7:29 am
thanks

so why even need the absolute sign.

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