1) isn't true. Are you sure you have copied the exercise correctly?
1) A1 A2 be two events, show that P (A1 ∩ A2) ≤ P (A1) . P (A2)
2) show that P (A1 ∩ A2 ∩ ... ... An) ≤ P (A1) . P (A2) . ... ... ... ... P (An)
4)
show that P (A + B) + P (/ A + / B) = 1
I have problems with these exercises. I dont know if I copied them wrong.
thanks