Unit 3 Flashcards
blank is a set of rules and operations for working with variables whose values are either 0
or 1
. Boolean algebra was defined by George Boole in the mid-19th century.
Boolean algebra
The area of computer science concerned with designing computer circuitry is called blank an indication of the vital role that logic plays in this field.
digital logic,
blank, denoted by *, applies to two elements from {0, 1} and obeys the standard rules for multiplication. The results of the multiplication operation are the same as the logical ∧ (“and”) operation.
Boolean multiplication
0 * 0 = blank
0
0 * 1 = blank
0
1 * 0 = blank
0
1 * 1 = blank
1
blank, denoted by +, applies to two elements from {0, 1} and obeys the standard rules for addition, except for 1 + 1.
Boolean addition
0 + 0 = blank
0
0 + 1 = blank
1
1 + 0 = blank
1
1 + 1 = blank
1
The blank of an element, denoted with a bar symbol, reverses that element’s value. Complementing a Boolean value is analogous to applying the ¬ (“not”) operation in logic.
complement
The blank is a logical operation that outputs 1 only when the inputs are different.
exclusive or or XOR operation
0 ⊕ 0 = blank
0
1 ⊕ 0 = blank
1
0 ⊕ 1 = blank
1
1 ⊕ 1 = blank
0
Variables that can have a value of 1 or 0 are called blank.
Boolean variables
blank can be built up by applying Boolean operations to Boolean variables or the constants 1 or 0.
Boolean expressions
blank takes precedence over Boolean addition.
The blank is applied as soon as the entire expression under the bar is evaluated.
blank can be used to override the precedence rules.
Boolean multiplication
complement operation
Parentheses
Two Boolean expressions are blank if they have the same value for every possible combination of values assigned to the variables contained in the expressions.
equivalent
In predicate logic, a special symbol (≡) is used to denote logical equivalence. In Boolean algebra, the blank is used to denote logical equivalence.
equal sign (=)
x + x = x
Idempotent laws
x * x = x
Idempotent law
To say x OR x—or to say x AND x—is redundant. In both cases, we just have x.
Idempotent laws
(x + y) + z = x + (y + z)
Associative laws
(xy)z = x(yz)
Associative laws
xy = yx
Commutative laws:
x + y = y + x
Commutative laws:
x + yz =(x + y)(x + z)
Distributive laws:
x(y + z) =xy + xz
Distributive laws: