The polynomial function is
.
(a)
\Find
and
.
Substitute at
in the polynomial function.
.

.
Substitute at
in the polynomial function.


.
and
.
(b)
\Intermediate value theorem :
\The function
is continuous on the closed interval
, let
be the number between
and
, where
then exist a number
in
such that
.
From (a) :
\\
and
.
Therefore
.
Then according to intermediate value theorem, there exist atleast one root such that
.
(c)
\An
- intrcepts
,The limits are
,
to four decimal places.
The polynomial function is
and intervals
.
Newtons approximation method formula :
.

Differentiate on each side with respect to
.

.
Newtons approximation method formula :
.
Consider root as
.
Newtons approximation :
.


For
.
Newtons approximation :
.

.
For
.
Newtons approximation :
.

.
For
.
Newtons approximation :
.


Since
and
are same to four decimal places, the root of equation
.
The root of the equation
.
(d)
\Graph :
\Graph the polynomial function
:
.gif\")
Observe the graph :
\The polynomial touches
-axis at
.
The root of the equation is
.
(e)
\Graph :
\Graph the polynomial function
:
\
.gif\")
Observe the graph :
\
satisfies the graph of the poynomial.
The root of the equation is
.
(a)
and
.
(b) There exist atleast one root in
such that
.
(c) The root of the equation is
..
(d)The root of the equation is
.
(e)
satisfies the graph of the poynomial.