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Question
I've heard that someone was figuring out a way of solving negative square roots. Is that true?

Yes.  The square-root of -1 is known as i.
This makes the square-root of -4 be 2i, the square-root of -9 be 3i, etc.
This leads to what is called imaginary numbers.

When the x-axis is real numbers and the y-axis is imaginary numbers,
the numbers in the plane are called complex numbers.

Using complex numbers, the system is complete.
Whole positive numbers and subtraction lead to negative positive numbers and 0.
Square-roots leads to more real numbers.
Using trig formulas, powers, or many other functions leads to all real numbers.
Taking the roots of negative numbers leads to complex numbers.
Doing any sort of math on complex numbers, however, leads to nothing else -
only different complex numbers.

To calculate square-roots, cube-roots, or any other root of a complex number, convert the number to polar coordinates.  That is, r is the distance to the origin and theta is the angle from the positive axis.  To find a cube-root, take the cube-root of r and divide the angle by 3.  Then add 120° and 240° to the result, and that will give the three cube-roots.

To find fourth-roots, compute the 4th root of r, and then divide the angle by 4.
Add 90°, 180°, and 270° to that angle to get the other 4th root.

For example, is the number is -8, then r = 8 and theta = 180°.
The cube roots would then be to find the cube-root of 8, which is 2,
and take 180°/3 = 60°.  The other cube roots would be at r=2, theta = 180° and
r = 2, theta = 300°.

Volunteer

#### Scott A Wilson

##### Expertise

I can answer any question in general math, arithetic, discret math, algebra, box problems, geometry, filling a tank with water, trigonometry, pre-calculus, linear algebra, complex mathematics, probability, statistics, and most of anything else that relates to math. I can also say that I broke 5 minutes for a mile, which is over 12 mph, but is that relevant?

##### Experience

Experience in the area; I have tutored people in the above areas of mathematics for over two years in AllExperts.com. I have tutored people here and there in mathematics since before I received a BS degree back in 1984. In just two more years, I received an MS degree as well, but more on that later. I tutored at OSU in the math center for all six years I was there. Most students offering assistance were juniors, seniors, or graduate students. I was allowed to tutor as a freshman. I tutored at Mathnasium for well over a year. I worked at The Boeing Company for over 5 years. I received an MS degreee in Mathematics from Oregon State Univeristy. The classes I took were over 100 hours of upper division credits in mathematical courses such as calculus, statistics, probabilty, linear algrebra, powers, linear regression, matrices, and more. I graduated with honors in both my BS and MS degrees. Past/Present Clients: College Students at Oregon State University, various math people since college, over 7,500 people on the PC from the US and rest the world.

Publications
My master's paper was published in the OSU journal. The subject of it was Numerical Analysis used in shock waves and rarefaction fans. It dealt with discontinuities that arose over time. They were solved using the Leap Frog method. That method was used and improvements of it were shown. The improvements were by Enquist-Osher, Godunov, and Lax-Wendroff.

Education/Credentials
Master of Science at OSU with high honors in mathematics. Bachelor of Science at OSU with high honors in mathematical sciences. This degree involved mathematics, statistics, and computer science. I also took sophmore level physics and chemistry while I was attending college. On the side I took raquetball, but that's still not relevant.

Awards and Honors
I earned high honors in both my BS degree and MS degree from Oregon State. I was in near the top in most of my classes. In several classes in mathematics, I was first. In a class of over 100 students, I was always one of the first ones to complete the test. I graduated with well over 50 credits in upper division mathematics.

Past/Present Clients
My clients have been students at OSU, people who live nearby, friends with math questions, and several people every day on the PC. I would guess that you are probably going to be one more.