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प्रश्न
Assertion (A): The value of \((\sin 80^{\circ}-\cos 80^{\circ})\) is positive.
Reason (R): \(45^{\circ}<\theta \leq 90^{\circ} \Rightarrow \sin \theta>\cos \theta\).
पर्याय
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 (А).
Assertion (A) is true and Reason (R) is false.
Assertion (A) is false and Reason (R) is true.
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उत्तर
Both Assertion (A) and Reason (R) are true and Reason (R) is a correct explanation of Assertion (A).
Explanation:
Step 1 – Assertion: A is true because \(80^{\circ}\) lies between \(45^{\circ}\) and \(90^{\circ}\), so \(\sin 80^{\circ}>\cos 80^{\circ}\). Therefore, their difference is positive.
Step 2 – Reason: R is true; for angles greater than \(45^{\circ}\) and at most \(90^{\circ}\), sine exceeds cosine.
Step 3 – Link: Applying R to \(\theta=80^{\circ}\) directly establishes A.
