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cattyroughie
05-11-2009, 08:44 PM
what is the square root of -48

DrMike
05-11-2009, 08:48 PM
what is the square root of -48

Amongst the real numbers, it has no square root.

Amongst the complex numbers, the answer is i\sqrt{48}=4\sqrt{3}i

cattyroughie
05-11-2009, 09:25 PM
thank you DrMike

DrMike
05-12-2009, 08:20 PM
You're welcome!

Petenerd
05-13-2009, 11:59 PM
First, find the square root of 48, which is 6.9282032302755091741097853660235. That is your answer, 6.9282032302755091741097853660235. :wink:

DrMike
05-14-2009, 12:32 AM
First, find the square root of 48, which is 2.44948974. Then just put the negative sign in front of it making it into a negative number, -2.44948974. :wink:

This is not correct. Eg, your method would give \sqrt{-4}=-2, but (-2)^2=(-2)\times(-2)=+4, not -4