The solution of $\frac{1}{2} +cosx + cos2x + cos3x + cos4x = 0$ is
The solution of $\frac{1}{2} +cosx + cos2x + cos3x + cos4x = 0$ is
- A
$x=\frac{2n\pi}{9},n\in I,n\neq 9m,m\in I$
- B
$x=\frac{2n\pi}{9},n\in I,n= 9m,m\in I$
- C
$x=\frac{n\pi}{9}+\frac{\pi}{2},n\in I$
- D
$x=\frac{2n\pi}{3}+\frac{\pi}{6},n\in I$
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