By Charlie, 11th Grader

How can numbers be imaginary? Are they ghosts or what?

Imaginary numbers are not ghosts, but they are also not real. They are not Real Numbers. Imaginary numbers are a type of number that can’t be found on a number line.

The letter “i” is always used to represent imaginary numbers, so it is never used as a variable like x, y, a, b, etc.

When you run into the square root of a negative, you hit a wall. What can you do? Not much without imaginaries. Once you define the square root of -1 to be i, then you can continue with the standard rules of algebra. Since i squared is -1, it brings you right back to the real numbers. Imaginaries enable you to break through that wall.

Even though they might seem a bit weird, imaginary numbers have a lot of real-life uses, especially in electricity and physics. They are also good for computer stuff. So, even though they might sound strange, imaginary numbers are actually pretty important for solving important problems in science and technology.