TS EAMCET · Maths · Trigonometric Equations
The value of the series \(\cos 12^{\circ}+\cos 84^{\circ}\) \(+\cos 132^{\circ}+\cos 156^{\circ}\) is
- A \(\frac{1}{2}\)
- B \(\frac{1}{4}\)
- C \(\frac{-1}{4}\)
- D \(\frac{-1}{2}\)
Answer & Solution
Correct Answer
(D) \(\frac{-1}{2}\)
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