Negative Square Roots on Calculators
Date: 10/30/95 at 14:44:17 From: Anonymous Date: Mon, 30 Oct 1995 15:07:48 ARG Every time I try to calculate on my calculator the square root of a negative number (-4, for example) I find the message "Error". Why? --- E-mail: firstname.lastname@example.org Buenos Aires - Argentina
Date: 10/31/95 at 17:6:35 From: Doctor Ken Subject: Re: (no subject) Hello! Well, that's because the way most people think about it, if you square any real number, you always get a positive number. So if you're trying to find the square root of a number (the inverse of squaring the number), you have to start out with a positive number. You actually _can_ do square roots of negative numbers if you're prepared to deal with things called "complex numbers." There you define a number i by the property that i^2 = -1. Then the square root of -4 would be 2i. But most calculators aren't fancy enough to handle stuff like that. -Doctor Ken, The Geometry Forum
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