MCQ
If the equations $2{x^2} + 3x + 5\lambda = 0$ and ${x^2} + 2x + 3\lambda = 0$ have a common root, then $\lambda = $
  • A
    $0$
  • B
    $-1$
  • $0, - 1$
  • D
    $2,-1$

Answer

Correct option: C.
$0, - 1$
c
(c) Given equations are $2{x^2} + 3x + 5\lambda = 0$ and ${x^2} + 2x + 3\lambda = 0$ have a common root if

$\frac{{{x^2}}}{{ - \lambda }} = \frac{x}{{ - \lambda }} = \frac{1}{1}$

==> ${x^2} = - \lambda ,x = - \lambda $or $\lambda = - 1,\,\,0$.

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