There are two cases to be considered.
CASE I : PDA M accepts by final state, Let 
Let qf be a new state not in Q. Consider the PDA 
where 
as well as the following transition.
contains 
and 
. It is easy to show that M and M' are equivalent i.e.
L(M) = L(
)
Let 
L(M) . Then 
for some 
and 
Then 
Thus accepts 