COMEDK · Maths · 8. Trigonometric Ratios & Identities
If \(\cos A=\dfrac{3}{4}\), then \(\left(32 \sin \dfrac{A}{2} \sin \dfrac{5 A}{2}\right)=\)
- A 16
- B 11
- C 8
- D 7
Answer & Solution
Correct Answer
(B) 11
Step-by-step Solution
Detailed explanation
Given \(\cos A = \dfrac{3}{4}\). The expression is \(32 \sin \dfrac{A}{2} \sin \dfrac{5A}{2}\). Using the product-to-sum formula \(2 \sin x \sin y = \cos(x - y) - \cos(x + y)\), we have:…
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