The value of $\arctan(0)$ is:
$$ \arctan(0) = 0 $$
Explanation:
The arctangent function, $\arctan(x)$, gives the angle $\theta$ such that $\tan(\theta) = x$. When $x = 0$, the angle $\theta$ is $0$ because $\tan(0) = 0$.
So,
$$ \arctan(0) = 0 $$
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