JEE MAIN - Mathematics (2002 - No. 40)
Product of real roots of equation $${t^2}{x^2} + \left| x \right| + 9 = 0$$
is always positive
is always negative
does not exist
none of these
説明
Product of real roots $$ = {9 \over {{t^2}}} > 0,\forall \,t\, \in R$$
$$\therefore$$ Product of real roots is always positive.
$$\therefore$$ Product of real roots is always positive.