Negation

Logic

• We can negate a variable by putting a negation symbol on it.
• ~p

If p is true then ~p is false.

If p is false then ~p is true.

Math

We do something similar with algebra, using the ‘-‘ symbol.

If a=3 then -a=-3.

If b=-4 then -b=4.

Appendix A

Be prepared for some confusion. The word negative might be used to signal that a value is less than 0 or it may be used to get the opposite of a variable in which case the result can be positive as we see in the above case for b equals -4.