The function is
.
The zero is
.
Synthetic Substitition :
\Perfom the synthetic substitution method to verify
is a zero of
.
The depressed polynomial is
.
Since
is a zero of
,
also a zero of
.
Perfom the synthetic substitution method to verify
on the obtained depressed polynomial.
Therefore
and
are the factors of
.
Using these
zeros and the new depressed polynomial from the last division, \ \
the polynomial can be written as
.
Identify Possible Rational Zeros :
\It is not practical to test all possible zeros of a polynomial function using only synthetic substitution.
\The Rational Zero Theorem can be used for finding the some possible zeros to test.
\The function is
.
Because the leading coefficient is
, the possible rational zeros are the integer factors of the constant term
.
Therefore, the possible rational zeros of
are
.
Synthetic Division:
\The function is
.
Perform the synthetic division method by testing
and
.

Since
, conclude that
is a zero of
.
Therefore
is a rational zero.
The new depressed polynomial is
.
Finding Rational Zeros :
\The remaining depressed polynomial is
which does not have rational zeros.
To find the rational zeros use the quadratic formula
.
Consider
.
Here
.
To find the rational zeros use the quadratic formula
.

The zeros of the depressed polynomial are
.
Therefore
and
are the two factors of the polynomial.
Therefore,
are the factors of
.
By using Factor theorem,
\When
then
is a factor of polynomial.
Factoring of
.
So
has five real zeros.
Zeros are
.
The linear factorization of
is
.
Zeros are
.