solve this ..................

1.
Proof:
Let  be a given polynomial function.
Then, by Polynomial remainder theorem,  is a divisor (factor) of  if and only if .

Hence,


Q.E.D.

2. 
Since  is a divisor of , there is exists  such that .
Hence, 
.
Therefore,


Now, let's find the roots of g(x):


Hence,

are solutions of f(x).