Exercise: Logical
operators
Boolean search statements
and
Venn diagrams
© Tefko Saracevic
1
Directions
• Slide 4 provides a Venn diagram
with numbered sets and a number
of search statements
– for each statement shade the
appropriate set or sets
– e.g. for (A OR B) AND C the sets
are 4, 5, 6
• Slide 5 is for practice
• Slide 6 has the answers
– BUT NOTE: one of the answers is
WRONG! Which one?
© Tefko Saracevic
2
Order of operations
• Rules for the order in which
operations are done effect the
answer - so follow them
• DIALOG order of operation is:
1. First are done all operations that are in
parentheses, then:
2. (W), (N), (S), (L), or (F)
3. NOT
4. AND
5. OR
• e.g. for A OR B AND C
– first is done B AND C
– and then A OR the results of B AND C
– thus this is the same as A OR (B AND C)
© Tefko Saracevic
3
Exercise: shade Venn diagrams
A
B
1
2
4
5
3
6
7
C
1. A AND B
2. A OR B
3. A OR B AND C
4. (A OR B) AND C
5. A AND B NOT C
6. A AND (B NOT C)
7. (A AND B) NOT C
8. (A NOT B) AND C
9. A NOT (B AND C)
10. A NOT B AND C
11. A AND (B OR C)
12. A AND B OR C
13. A OR (B AND C)
14. A OR B OR C
15 A AND B AND C
© Tefko Saracevic
4
Practice page
A
B
2
3
1
4
5
6
7
C
© Tefko Saracevic
5
Venn diagrams: solutions
p.s. one of them is wrong!
A
B
1
2
4
5
3
6
7
C
1. A AND B
2,5
2. A OR B
1,2,3,4,5,6
3. A OR B AND C
1,2,4,5,6
4. (A OR B) AND C
4,5,6
5. A AND B NOT C
2
6. A AND (B NOT C)
2
7. (A AND B) NOT C
2
8. (A NOT B) AND C
4
9. A NOT (B AND C)
6
10. A NOT B AND C
4
11. A AND (B OR C)
2,4,5
12. A AND B OR C
2,4,5,6,7
13. A OR (B AND C)
1,2,4,5,6
14. A OR B OR C
1,2,3,4,5,6,7
15 A AND B AND C
5
© Tefko Saracevic
6
well…it is a Venn diagram too
from angelfire.com
© Tefko Saracevic
7
description
• This Venn diagram is color-coded in order to
demonstrate the way in which the layers
overlap--if you are not familiar with the way
colors are mixed subtractively just enjoy all
the pretty colors. Not all Venn diagrams are
color-coded.
• Each circle is clearly labeled with the name of
a character in bold letters. The qualities of
that character are then written in that circle.
• Some qualities are in an area where two
circles overlap because both characters share
those qualities. For instance, both the
Tazmanian Devil and Wile E. Coyote are
mammals, so "mammal" goes in the purple
area where the circles of the two characters
overlap.
• In the center, all the circles overlap; qualities
in this area this are shared by all three
characters. For instance, Elmer Fudd, Wile E.
Coyote, and the Tazmanian Devil were all in
the movie Space Jam, so "Space Jam is
written in the area where all the circles
overlap.
© Tefko
• Saracevic
8