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Which one of the following could $x$ not equal for the equation below?

$$\csc\left(\cfrac{5\pi}{6}\right)=\csc(x)$$

$-\cfrac{7\pi}{6}$

$\cfrac{\pi}{6}$

$-\cfrac{\pi}{6}$

$\cfrac{13\pi}{6}$

$-\cfrac{19\pi}{6}$