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The only value of k for which the quadratic polynomial kx2 + x + k has equal zeros is 12 - Mathematics

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Question

The only value of k for which the quadratic polynomial kx2 + x + k has equal zeros is `1/2`

Options

  • True

  • False

MCQ
True or False
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Solution

This statement is False.

Explanation:

It is given that the quadratic polynomial kx2 + x + k has equal zeroes.

∴ b2 – 4ac = 0

i.e., discriminant is zero

`\implies` (1)2 – 4(k)(k) = 0

`\implies` 1 – 4k2 = 0

`\implies` 4k2 = 1

`\implies` k = `1/4`

`\implies` k = `+- 1/2`

So, for two values of k, given quadratic polynomial has equal zeroes.

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Chapter 2: Polynomials - Exercise 2.2 [Page 12]

APPEARS IN

NCERT Exemplar Mathematics [English] Class 10
Chapter 2 Polynomials
Exercise 2.2 | Q 2.(vii) | Page 12

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