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Question
Assertion (A): The polynomial $$p(x)=(x^{3}+x)$$ has one real zero.
Reason (R): A polynomial of nth degree has at most n zeros.
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
Both Assertion (A) and Reason (R) are true but Reason (R) is not a correct explanation of Assertion (A).
Explanation:
Both statements are true.
To identify the real zero, factor the polynomial:
$$x^{3}+x=x(x^{2}+1)$$
For real $$x$$, $$x^{2}+1>0$$, so the only real zero is $$x=0$$. The Reason states only that a cubic polynomial has at most three zeros; this does not explain why this polynomial has exactly one real zero.
