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Chapter 7: Probability
Complement of an Event
Sometimes it is more convenient to consider what is outside of a given event
than to consider what is inside the given event itself. This deals with the
concept we refer to as the complement of an event.
Definition: Complement of an Event
The complement of an event A is the set of all outcomes that are not in A.
The complement of A is denoted by A
C
.
Note:
Some authors will use the notation
A
/
instead of
A
c
to represent the
complement of the event
A
.
The diagram in
Figure 7-15
depicts the complement of the event
A
.
Figure 7-15:
Venn diagram depicting
the complement of the
event
A