WBJEE · Maths · Trigonometric Ratios & Identities
The value of \(\cos ^{2} 75^{\circ}+\cos ^{2} 45^{\circ}+\cos ^{2} 15^{\circ}\) \(-\cos ^{2} 30^{\circ}-\cos ^{2} 60^{\circ}\) is
- A 0
- B 1
- C \(\frac{1}{2}\)
- D \(\frac{1}{4}\)
Answer & Solution
Correct Answer
(C) \(\frac{1}{2}\)
Step-by-step Solution
Detailed explanation
Given \(\cos ^{2} 75^{\circ}+\cos ^{2} 45^{\circ}+\cos ^{2} 15^{\circ}-\cos ^{2} 30^{\circ}\cos^260^\circ\)…
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