Mutually exclusive events: The intersection of events A and B is null. A and B are mutually exclusive events, also known as mutually exclusive events. It can also be described as events that cannot happen at the same time. A∩B Impossible event (A ∩ b = φ) means that event A and event B are mutually exclusive, which means that the trials of event A and event B will not appear at the same time.

BR/>； Opposing events are also called "inverse events that are unlikely to happen at the same time".

If it is impossible to cross B, events A and B are inevitable events, called events A and B, which are opposite. It means that event A and event B only appear once in any test.

Definition: It must be two mutually exclusive events, opposing events.