At least two heads and exactly one head should be mutually exclusive events, because the sum of the probabilities of these two events is not equal to 1.

The concept of opposing events is

If a and b are impossible events and a and b are inevitable events, then event a and event b are opposite events, that is to say, event a and event b only occur once in any experiment.

The relationship between the probabilities of opposing events:

P(A)+P(B)= 1

Throw three coins. * * * Yes.

1 one positive and two negative

Two positive and one negative.

3 sanzheng

4 Three opposites

At least twice, in the case of 2 and 3, and just once, in the case of 1

If at least two fronts are regarded as an event A and exactly one front is regarded as an event B, then the intersection of A and B is an empty set. Events A and B are mutually exclusive, but P(A)+P(B) is not equal to 1, and there are three opposites. So, it should be mutually exclusive events.

The opposing event must be mutually exclusive events, but mutually exclusive events is not necessarily an opposing event.