What is $\sqrt{-2\cdot(-3)}$ ? Whether it is $-\sqrt 6$ or $\sqrt 6$?

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    $\begingroup$ I reckon that $\sqrt 6$ is $\sqrt6$. $\endgroup$ – Lord Shark the Unknown Nov 3 '18 at 12:41
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    $\begingroup$ Since you tagged this complex-numbers the answer is Both :-) Complex numbers simply don't have unique square roots. If you intended the question to be about real numbers then the square roots are always non-negative by convention. $\endgroup$ – Jyrki Lahtonen Nov 3 '18 at 12:42
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    $\begingroup$ Also, 1) search the site, we have several questions about misunderstandings related to roots of complex numbers, their multi-valuedness in particular. 2) Please study our guide for new askers. You see, the founder of this place says that this place is a Wiki first. Does it look like this question adds something to a Wiki? $\endgroup$ – Jyrki Lahtonen Nov 3 '18 at 12:47

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