The equation is
.
Consider
.
Rational zeros method:
\Rational Root Theorem, if a rational number in simplest form
is a root of the polynomial equation
, then
is a factor of
and
is a factor if
.
If
is a rational zero, then
is a factor of
and
is a factor of
.
The possible values of
are
.
The possible values for
are
.
So,
.
Consider
.
Substitute
in
.
.
Since
,
is not a zero of
.
Consider
.
Using synthetic division:
\
Since
,
is a zero of
.
is a factor of
.
The depressed polynomial is
.
.
Consider
.
If
is a rational zero, then
is a factor of
and
is a factor of
.
The possible values of
are
.
The possible values of
are
.
So,
.
.
,
is not a zero of
.

,
is not a zero of
.
Consider
.
Using synthetic division:
\
,
is a zero of
.
is a factor of
.
The depressed polynomial is
.
.
The solutions of
are imaginary.
The real solutions of
are
.
.