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Question
Assertion (A): If $$\alpha$$ and $$\beta$$ be the zeros of polynomial $$(x^{2}-6x+k)$$ such that $$(\alpha-\beta)=2$$ then $$k=8$$.
Reason (R): If $$\alpha$$ is a zero of the polynomial $$p(x)$$ then $$p(-\alpha)=0$$.
Options
Both Assertion (A) and Reason (R) are true and Reason (R) is a correct explanation of Assertion (A).
Both Assertion (A) and Reason (R) are true but Reason (R) is not a correct explanation of Assertion (A).
Assertion (A) is true and Reason (R) is false.
Assertion (A) is false and Reason (R) is true.
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Solution
Assertion (A) is true and Reason (R) is false.
Explanation:
Step 1 – Assertion: A is true. By the sum of zeros, $$\alpha+\beta=6$$.
Combining this with $$\alpha-\beta=2$$ gives $$\alpha=4$$ and $$\beta=2$$.
Substituting $$\alpha=4$$ into the polynomial gives:
$$4^{2}-6(4)+k=0$$
$$16-24+k=0\Rightarrow k=8$$
Step 2 – Reason: R is false. A zero $$\alpha$$ of $$p(x)$$ implies $$p(\alpha)=0$$, not necessarily $$p(-\alpha)=0$$.
