nm97 wrote:
What is the range of values for \(x^2\) given that (\(x^2\)+4)(\(x^2\)-2)<0?
(A) -4 < \(x^2\) < 2
(B) 0 ≤ \(x^2\) ≤ 2
(C) 0 ≤ \(x^2\) < 2
(D) 0 < \(x^2\) < 2
(E) -∞ < x < 2
basic clue or trick to solve this question is to check our desired outcome using given options
we need is (\(x^2\)+4)(\(x^2\)-2)<0
so x has to be <2 ; it cannot be =2 as then (\(x^2\)+4)(\(x^2\)-2)<0 wont stand true
so negate options A,B
also
value x^2 cannot be-ve so option E negated
between option C & D
we can note that (\(x^2\)+4)(\(x^2\)-2)<0 will hold true when x^2=0 so IMO C is correct