The abs() command returns the absolute value of an expression. The absolute value of a real number is the number of units from 0 the number is. The absolute value of 7 for example is 7 becasue it is that many units away from zero. The absolute value of -7 however is 7. So it in a way gets rid of the negative.
The absolute value of a complex or imaginary number can also be taken, but it is done a little differently. If a complex number is written a+bi, then the absolute value of the number is √(a2+b2).
abs(5) 5 abs(-5) 5 abs(3+4i) 5
- Negation ( - )