1.随机事件的判断在一定条件下,有些事件必然会发生,这样的事件称为必然事件,有些事件必然不会发生,这样的事件称为不可能事件,必然事件与不可能事件统称确定性事件.在一定条件下,可能发生也可能不发生的事件称为随机事件.若A为必然事件,则P(A)=1,若B为不可能事件,则P(B)=0.例1在一个不透明的袋子中装有仅颜色不同的10个小球,其中红球4个,黑球6个.先 1. Judgments of random events Under certain conditions, some events are bound to occur. Such events are called inevitable events. Some events are inevitable. Such events are called impossible events. Both inevitable events and impossible events are collectively referred to as certainty Under certain conditions, events that may or may not occur are called random events, P (A) = 1 if A is a necessary event, and P (B) = 0 if B is an impossible event 1 in an opaque bag with only different colors of the 10 balls, of which 4 red balls, black ball 6. First