GMAT PREP 1 - PS
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- gmat740
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Square root of a number is always +/-
eg: square root of 4= 4^0.5 = +2 and -2
so sq-rt(x^2) has to be +x and -x
and |x| = +x when x>0 and -x when x<0
so E is clearly an answer
Hope it helps
eg: square root of 4= 4^0.5 = +2 and -2
so sq-rt(x^2) has to be +x and -x
and |x| = +x when x>0 and -x when x<0
so E is clearly an answer
Hope it helps
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This is not true. the square root function will only return a positive value (or zero).gmat740 wrote:Square root of a number is always +/-
eg: square root of 4= 4^0.5 = +2 and -2
so sq-rt(x^2) has to be +x and -x
So √(x^2) = |x|, and thats why the answer is E.
-BM-
- gmat740
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The number inside a square root is always positive(otherwise we will have complex roots, i or w etc if you are from engineering background you will be knowing about this )
However,
The number we get after taking a square root can be positive as well as negative
You need to check it again BM
regards
Karan
However,
The number we get after taking a square root can be positive as well as negative
You need to check it again BM
regards
Karan
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- Master | Next Rank: 500 Posts
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Karan, have a look at the explanation by Ian in this post:gmat740 wrote:The number inside a square root is always positive(otherwise we will have complex roots, i or w etc if you are from engineering background you will be knowing about this )
However,
The number we get after taking a square root can be positive as well as negative
You need to check it again BM
regards
Karan
https://www.beatthegmat.com/difference-b ... 12863.html
-BM-
- gmat740
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BM,
I just saw the post you referred to, and I wonder,Is the GMAT maths different from the fundamental Maths which we learn in our school!!
I don't know how many times basic fundamental rules change in GMAT,but may be like this I am going to have a very low score because I don't take any tutorials for GMAT,considering that GMAT follows the same fundamental rules of maths as followed elsewhere, but seems like I am making a mistake
Thanks For Pointing me
Karan
I just saw the post you referred to, and I wonder,Is the GMAT maths different from the fundamental Maths which we learn in our school!!
I don't know how many times basic fundamental rules change in GMAT,but may be like this I am going to have a very low score because I don't take any tutorials for GMAT,considering that GMAT follows the same fundamental rules of maths as followed elsewhere, but seems like I am making a mistake
Thanks For Pointing me
Karan