Square Roots, Complex NumbersDate: Sat, 15 Jun 1996 00:03:07 -0400 (EDT) From: Anonymous Subject: Square Roots x^2 = -9 I tried taking the square root of both sides. Is this impossible? Date: Sat, 15 Jun 1996 09:25:18 -0400 (EDT) From: Dr. Ethan Subject: Re: Square Roots Hello, It depends on what you mean by impossible. If you want the answer to be a real number like ones you are used to (like 2, 3.769, 17.55555.. , Pi, etc.) then it is impossible, but mathematicians have come up with a whole area of mathematics and a whole system of numbers that has no problem with x^2 = -9. They are called complex numbers. They use the symbol i to denote the square root of -1 so in your problem, x = 3i. If you would like more information on complex numbers, write back and ask. -Doctor Ethan, The Math Forum |
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