Probability question bank (Quantitative Aptitude)

Two coins are tossed. Let $A$ be the event that the first coin shows head and $B$ be the event that the second coin shows a tail. The two events $A$ and $B$ are:

If $P(A_1 \cup A_2) = 1 - P(A_1^c) P(A_2^c)$,where $c$ stands for complement,then the events $A_1$ and $A_2$ are