COMEDK · Maths · 8. Trigonometric Ratios & Identities
The value of \(\dfrac{\sin ^2 20^{\circ}+\cos ^4 20^{\circ}}{\sin ^4 20^{\circ}+\cos ^2 20^{\circ}}\) is
- A \(2\)
- B \(0\)
- C \(\dfrac{1}{2}\)
- D \(1\)
Answer & Solution
Correct Answer
(D) \(1\)
Step-by-step Solution
Detailed explanation
Let \(\theta = 20^{\circ}\). The expression is \(E = \dfrac{\sin^{2}\theta + \cos^{4}\theta}{\sin^{4}\theta + \cos^{2}\theta}\). Using the identity \(\sin^{2}\theta = 1 - \cos^{2}\theta\), we substitute into the numerator: Numerator…
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