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If the sum of the roots of the equation x2 − x = λ(2x − 1) is zero, then λ =

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Question

If the sum of the roots of the equation x2 − x = λ(2x − 1) is zero, then λ =

Options

  • −2

  • 2

  • \[- \frac{1}{2}\]

  • \[\frac{1}{2}\]

MCQ
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Solution

Equation is x2 − x = λ (2x − 1)

x2 – x – λ (2x – 1) = 0 

x2 – (2λ + 1)x + λ = 0

Here a = 1, b = – (2λ + 1), c = λ 

Sum of the roots = `– b/a`

⇒ – (– (2λ + 1)) = 0 

⇒ λ = `– 1/2`

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Chapter 4: Quadratic Equations - Exercise 4.15 [Page 84]

APPEARS IN

R.D. Sharma Mathematics [English] Class 10
Chapter 4 Quadratic Equations
Exercise 4.15 | Q 17 | Page 84

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