In the set of real numbers, negative numbers do not have square roots. A new kind of number, called imaginary was invented so that negative numbers would have a square root. These numbers start with the number i, which equals the square root of -1, or i2 = -1.

All imaginary numbers consist of two parts, the real part, b, and the imaginary part, i. Example:

1. Simplify: SQRT(-5)

Solution: Write -5 as a product of

prime factors.

SQRT(-1 * 5)

Write as separate square roots.

(SQRT(-1))(SQRT(5))

By definition, i = SQRT(-1),

so the final answer is

(SQRT(5))i. (SQRT(5)

is the real part, or b.)

I just dont get this entire thing... how does it even work?