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JEE MAIN 2022
27-06-2022 S1
Question
The value of $\cos \left(\frac{2 \pi}{7}\right)+\cos \left(\frac{4 \pi}{7}\right)+\cos \left(\frac{6 \pi}{7}\right)$ is equal to:
Select the correct option:
A
–1
B
-1/2
C
-1/3
D
-1/4
✓ Correct! Well done.
✗ Incorrect. Try again or view the solution.
Solution
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Showing 18 questions
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