NCERT Exemplar Solutions
Class 10 - Mathematics - CHAPTER 2: Polynomials - Exercise 2.1
Question 8

Question.  8

The zeroes of the quadratic polynomial \(x^2 + kx + k\), where \(k \ne 0\), are:

(A)

cannot both be positive

(B)

cannot both be negative

(C)

are always unequal

(D)

are always equal

Detailed Answer with Explanation:

Step 1: Recall relations between coefficients and zeroes.

For a quadratic \(x^2 + kx + k\):

Sum of zeroes = \(-k\).

Product of zeroes = \(k\).

Step 2: Assume both zeroes are positive.

If both are positive, then:

Sum > 0 ⇒ \(-k > 0\) ⇒ \(k < 0\).

Product > 0 ⇒ \(k > 0\).

This is a contradiction (\(k\) cannot be both positive and negative at the same time).

Step 3: Conclusion.

It is impossible for both zeroes to be positive.

Correct Option: (A) cannot both be positive

NCERT Exemplar Solutions Class 10 – Mathematics – CHAPTER 2: Polynomials – Exercise 2.1 | Detailed Answers