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Question

Mathematics Question on Polynomials

Assertion (A): Zeroes of a polynomial p(x)=x22x3p(x) = x^2 − 2x − 3 are -1 and 3.
Reason (R): The graph of polynomial p(x)=x22x3p(x) = x^2 − 2x − 3 intersects the x-axis at (-1, 0) and (3, 0).

A

Both, Assertion (A) and Reason (R) are true. Reason (R) explains Assertion (A) completely.

B

Both, Assertion (A) and Reason (R) are true. Reason (R) does not explain Assertion (A).

C

Assertion (A) is true but Reason (R) is false.

D

Assertion (A) is false but Reason (R) is true.

Answer

Both, Assertion (A) and Reason (R) are true. Reason (R) explains Assertion (A) completely.

Explanation

Solution

- The given polynomial is p(x)=x22x3p(x) = x^2 - 2x - 3. To find the zeroes, we solve x22x3=0x^2 - 2x - 3 = 0 by factoring:

x22x3=(x3)(x+1)=0x^2 - 2x - 3 = (x - 3)(x + 1) = 0

Thus, the zeroes of the polynomial are x=3x = 3 and x=1x = -1.

- The graph of a quadratic polynomial intersects the xx-axis at its zeroes. Therefore, the points where the graph intersects the xx-axis are (1,0)(-1, 0) and (3,0)(3, 0), as given in the reason.

Since both the assertion and the reason are true, and the reason explains the assertion, the correct answer is (a).