The function is
.
Identify Possible Rational Zeros of
:
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 polynomial function is
.
Use rational zero theorem to find the potential rational zeros of a polynomial function.
\If
is the rational zero, then
is factor of the constant term
and
is factor of the leading coefficient
.
The possible values of
are
and
.
The possible values of
are
.
Now form all possible ratios of
are
and
.
Make a table for the synthetic division and test possible zeros.
\\
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Since
,
is one of the zero of the function.
\
The depressed polynomial is
.
is a one of factor of the function
.
is a zero of
.
\
Find the roots of the polynomial
by using quadratic formula.
Quadratic formula:
.
Substitute
,
and
in the above expression.
\
\
Therefore,
and
are also the factors of
.
Therefore roots of
are
and
.
are complex zeros of
.
\

The complex zeros are
.
Factor form of
is
.