For which of the following values of x is
(sq. root of 1  (sq. root of 2  (sq. root of x)))
NOT defined as a real number?
A) 1
B) 2
C) 3
D) 4
E) 5[/b]
Sq. Root Problem
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The correct ans. is E) 5 ...
(sq. root of 1  (sq. root of 2  (sq. root of x)))
D) 4 is incorrect as it leads to a REAL number unlike E) 5
(sq. root of 1  (sq. root of 2  (sq. root of x)))
D) 4 is incorrect as it leads to a REAL number unlike E) 5

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All the choices lead to real numbers.
when x= 1==> sqrt(1)  (Sqrt(2) Sqrt(1))
==> 2 Sqrt(2)
Irrational number. But real number.
Similarly for all other choices.
If the number is not a real number it need to be either imaginary number or complex number.
Thanks
Raama
when x= 1==> sqrt(1)  (Sqrt(2) Sqrt(1))
==> 2 Sqrt(2)
Irrational number. But real number.
Similarly for all other choices.
If the number is not a real number it need to be either imaginary number or complex number.
Thanks
Raama

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The problem is from one of the GMAT Prep exams ... per the earlier explanation the answer is 5 because it leads to a square root of a negative which isn't a real number.