Represent each number by the simplest numeral, without using an absolute value symbol?

Question

l (-6)-0 l

neg. or pos.???

Answer 1

It's 6, or + 6 if you prefer to make its positive nature explicit.

(Some would consider that overkill.)

That's because (- 6) - 0 = - 6, and l - 6 l = 6, because

' l z l ' with z real means the ABSOLUTE value --- that is an intrinsically POSITIVE quantity --- corresponding to the argument z. That ABSOLUTE value is defined as follows:

If z is a positive real number, l z l = z;

if z is a negative real number, l z l = - z.

In both of these cases, the end result is POSITIVE.

It's that simple!

Live long and prosper.

Answer 2

The absolute value symbol makes it positive:
6