When explaining about Independent event we’ll consider two events first and in a space. For example, if those two events are A and B respectively,and they are situated in a space S then they are said to be independent. But remember, if P (AB) = P (A).P (B).
So separate them one by one as:
P(A) = P(A I B) = P(A I B)
P(B) = P(B I A)= P(B I A)
For n independent events A1,A2 ,… ,An
P (A1… A2···An) = P (A1) P (A2) … P (An).