A root can only have a negative value if it is an odd root

[eloka]

and the base of the root is negative..(from Manhattan GMAT)

However, according to other gmat preps

root -1 or root -27 are imaginary number.

can we count any root imaginary number?

is imaginary number countable?

[thinkpanther]

Hi Eloka,

Below is how this works:

root of a negative number is real only if the root is odd, (3,5,7,9 etc)

Eg. cube root (-27) or (-27)^(1/3) = -3 or -3*-3*-3 = -27

root in general english refers to square root or ^(1/2)

sqrt(-27) or sqrt(-1) is not allowed and hence imaginary

HTH