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Complex Numbers and Quadratic Equations — Maths STD 11 Science — Question

CBSE BoardEnglish MediumSTD 11 ScienceMathsComplex Numbers and Quadratic Equations1 Mark
MCQ
A quadratic equation $ax^2 + bx + c = 0$ has two distinct real roots, if
  • A
    $a = 0$
  • B
    $b^2- 4ac = 0$
  • C
    $b^2 - 4ac < 0$
  • ✓
    $b^2- 4ac > 0$
✓

Answer

Correct option: D.
$b^2- 4ac > 0$
If $a = 0,$ it becomes linear equation.
If $b^2 - 4ac = 0$, then there will be real and equal roots.
If $b^2 - 4ac < 0,$ then the roots will be unreal.
Only if $b^2 - 4ac > 0,$ we will get two real distinct roots.
Option $D$ is correct!

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