## Truth Tables and De Morgan's Rules

Read this chapter, which discusses Boolean variables as used in decision tables. Truth tables are used to collect variables and their values relative to decisions that have to be made within control structures.

### 19. Not at the Beginning and Not in the Middle of the Chapter

Answer:Using the De Morgan Rule

`!(A && B)`

is equivalent to`!A || !B || !C`

The expression

boolean noDriving = !(daylight && passenger.age >= 21 && passenger.licensed );is equivalent to

boolean noDriving = !daylight || !(passenger.age >= 21) || !passenger.licensed ;which can be further transformed to

boolean noDriving = !daylight || passenger.age < 21 || !passenger.licensed ;

# Not at the Beginning and Not in the Middle of the Chapter

If you are not interested or do not have the time, you may not wish to review the following.

- truth table Truth tables.
- truth tables, row order Conventional order of truth table rows.
- De Morgan, Rules De Morgan's Rules with two operands.
- De Morgan, Rules, three operand De Morgan's Rules with three operands.