The rational function is .
Replce by
.
Step 1: Factor the numerator and denominator of . Find the domain of the rational function.
\
The rational function .
\
.
Domain : Domain of the function is the set of values of which makes the function mathematically correct.
.
Denominator of the function should not be zero.
\Domain of the function is defined for all values of except at
.
Domain of the function is .
Step 2: Write in lowest terms.
\
The rational function in lowest terms is .
Step 3: Locate the intercepts of the graph.
\Find intercepts.
\The -intercepts are the zeros of the numerator of
that are in the domain of
.
To find -intercept, substitute
.
or
\
-intercepts are
,
.
Determine the behavior of the graph of near each
-intercept.
Near :
.
Plot the point and indicate a line with positive slope.
Near :
. \ \
Plot the point and indicate a line with negative slope.
Find the -intercept, substitute
.
\
\
The -intercept is
.
\
Step 4: Determine the vertical asymptotes.
\The rational function is .
The Vertical asymptote can be found equating denominator to zero.
\
\
Vertical asymptote .
\
\
Step 5: Determine the horizontal or oblique asymptote.
\To find horizontal asymptote, first find the degree of the numerator and the degree of denominator.
\\
Degree of numerator, Degree of the denominator
.
Since the degree of the numerator is greater than degree of denominator, there is no horizontal asymptote.
\Find oblique asymptote.
\Oblique asymptote is found by long division.
\
Quotient is oblique asymptote.
\\
Oblique asymptote is .
\
\
Step 6: Use the zeros of the numerator and denominator of to divide the
-axis into intervals
\
The real zero of numerator is and
and the real zeros of denominator
\
So the real zeros are divide the - axis into four intervals.
\
\
\
Choosing a number for in each interval and evaluating
.
Interval | \ \
| \
\
\ | \
\
| \
Location of graph | \
\
| \
\
| \
\
| \
\
| \
Below the \
| \
\
| \
\
| \
\
\ | \
\
| \
Above the \
| \
\
| \
\
| \
\
\ \ \ \
| \
\
| \
Below the \
| \
\
| \
\
| \
\
\ | \
\
| \
Above the \
| \
\
\
Step 7 : Analyze the behavior of the graph of near each asymptote and indicate this behavior on the graph.
The graph of is below
-axis for
and above
-axis for
, hence the graph does not intersect the oblique asymptote.
The graph of is above
-axis in interval
, hence the graph approaches to vertical asymptote at
.
The graph of is below
-axis in interval
and is above
-axis in interval
, hence the graph approaches the oblique asymptote.
\
Graph :
\The function .
\
Domain of the function is .
-intercepts are
,
.
Plot the point and indicate a line with positive slope.
Plot the point and indicate a line with negative slope.
The -intercept is
.
Vertical asymptote .
Oblique asymptote is .
And point on the graph are
\\
\
\
Graph of the rational function : \ \