# Multiplying two negative numbers inside a square root

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

• I reckon that $\sqrt 6$ is $\sqrt6$. – Lord Shark the Unknown Nov 3 '18 at 12:41
• 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. – Jyrki Lahtonen Nov 3 '18 at 12:42
• 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? – Jyrki Lahtonen Nov 3 '18 at 12:47