# Math Help - infinitisimal and infinity

1. ## infinitisimal and infinity

Hi,

I have a question. Let's say an experiment has a very little probability of giving the result A and that probability is either (treat every case separately) :

1) it is a very small number but it is a real number.

2) it tends to zero

If we try the experiment an infinite number of times, does one of the possibilities (1) or 2)), neither or both give at least one time the result A with probability 1 (it means we are sure it happens at least once) ? (I guess the 1) works but I am not so good at prob.)

thanks

2. ## Probability

If we do the experiment 'n' times, Result A appeared at least once time's probability is P(n)=1-(1-p)^n,where 'p' is the probability of A in one experiment, so If we try the experiment an infinite number of times, P(n)=1,we are sure it happens at least once , but if the experiment time is limited the answer is (1).