Identify Possible Rational Zeros:
\Usually 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 equation is
.
Because the leading coefficient is
, the possible rational zeros are the intezer factors of the constant term
.
Therefore the possible rational zeros are
.
Consider
.
Perform the synthetic substitution method by testing
and
.

By using synthetic substitution, it can be determined that
is a rational zero.
The depressed polynomial is
.
Consider
.
Perform the synthetic substitution method on the depressed polynomial by testing
and
.

By using synthetic substitution, it can be determined that
is a rational zero.
The new depressed polynomial is
.
Consider
.
Perform the synthetic substitution method on the depressed polynomial by testing
and
.

By using synthetic substitution, it can be determined that
is a rational zero.
Therefore
are the factors of the equation.
The final quotient can be written as
.
Factoring the quadratic expression yeilds
.
Zeros are
.
The zeros of the equation are
.