TS EAMCET · Maths · Trigonometric Ratios & Identities
\(\cos 18^{\circ}=\)
- A \(\frac{1}{8}(5-\sqrt{5})\)
- B \(\frac{1}{2 \sqrt{2}} \sqrt{5+\sqrt{5}}\)
- C \(\frac{\sqrt{5}-1}{4}\)
- D \(\frac{\sqrt{5}+1}{4}\)
Answer & Solution
Correct Answer
(B) \(\frac{1}{2 \sqrt{2}} \sqrt{5+\sqrt{5}}\)
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