anilisanil wrote:
nikhil007 wrote:
Bluelagoon wrote:
you are explicitly saying that n is positive square root of 36 which is +6. If you try to take the square root of a negative number than that square root takes you to the concept of imaginary numbers. GMAT is not concerned with it and hence you will never see something like n^2 = -36.
Yes I am explicitly saying that because for \(\sqrt{36}\) as per Gmat -6 shouldn't be an option other wise if your are given statement like x= \(\sqrt{36}\) you will have to consider 2 roots +-6, whereas we say that even square root will only have positive number as a answer in Gmat, coz -6 is imaginary
- 6 is NOT imaginary, SQUARE ROOT (or any even root) of a negative integer is imaginary (imaginary numbers are out of scope for GMAT).
Guys, could you please point me to the instructions where we are asked to consider only positive roots for numbers?
Any nonnegative real number has a
unique non-negative square root called
the principal square root and unless otherwise specified,
the square root is generally taken to mean
the principal square root.
When the GMAT provides the square root sign for an even root, such as \(\sqrt{x}\) or \(\sqrt[4]{x}\), then the
only accepted answer is the positive root.
That is, \(\sqrt{25}=5\), NOT +5 or -5. In contrast, the equation \(x^2=25\) has TWO solutions, \(\sqrt{25}=+5\) and \(-\sqrt{25}=-5\).
Even roots have only non-negative value on the GMAT.