JEE Main 2014 · 9 Apr · Shift 1 · Mathematics Q63

← JEE Main 2014 · 9 Apr · Shift 1

MathematicsSingle correct+4 / -1Question 63 of 90

If equations $ax^2+bx+c=0$ , ( $a,b,c\in\mathbf R$ , $a\ne0$ ) and $2x^2+3x+4=0$ have a common root, then $a:b:c$ equals :

1 : 2 : 3

2 : 3 : 4

4 : 3 : 2

3 : 2 : 1

Answer and worked solution

Official answer: B

$2x^2+3x+4=0$ has discriminant $9-32<0$ , so its roots are a non-real conjugate pair. A real-coefficient quadratic sharing one of them shares both, so the two equations are proportional: $a:b:c=2:3:4$ .

Topics:Nature of roots Roots and coefficients

← Previous question Next question →

JEE Main 2014 · 9 Apr · Shift 1, Mathematics question 63