The function is .
Factor the numerator and denominator of . Find the domain of rational function.
.
The domain of a rational function is the set of all real numbers except those for which the denominator is .
To find which number make the fraction undefined create an equation where the denominator is not equal to .
The domain of is
.
Write in lowest terms:
.
Locate the intercepts of the graph and determine the behavior of the graph of near each
- intercept :
Change to
.
Find the intercepts :
\Find the -intercept by equating the numerator to zero.
-intercept is
.
Behavior at -intercept:
.
Plot the point and draw a line through
with a negative slope.
Find the -intercept by substituting
in the
.
.
-intercept is
.
\
Determine the vertical asymptotes :
\Find the vertical asymptote by equating denominator to zero.
\
Vertical asymptote is at .
\
.
The function not defined at .
.
Hole at .
\
Determine the horizontal asymptotes / oblique asymptotes:
\To find horizontal asymptote, first find the degree of the numerator and degree of the denominator.
\Degree of the numerator and degree of the denominator
.
Since the degree of the numerator is equal to the degree of the denominator, horizontal asymptote is the ratio of leading coefficient of numerator and denominator.
\Horizontal asymptote is at .
The graph does not intersect the line .
Use the zeros of the numerator and denominator of to divide the
-axis into intervals:
Real zeros of the numerator is at and
.
Real zeros of the denominator is at and
.
Use these values to divide the -axis into four intervals.
,
,
and
.
Interval | \ \
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Number chosen \ | \
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Value of | \
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Location of graph \ | \
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\ Above \ | \
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Below | \
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Below | \
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Above | \
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Point of graph \ | \
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The graph of is above the
-axis for
.
The graph of does not intersect the graph of horizontal asymptote at
. Therefore the graph of
will approach
from
and will approach the vertical asymptote at
at the bottom from the left.
The graph of is below the
-axis for
, the graph of will approach
at the bottom from the left.
Since the graph of is above the
-axis for
and does not intersect the graph of horizontal asymptote at
, the graph of
will approach
from
.
Use the results obtained in Steps 1 through 7 to graph the function :
\The graph of :
1:
The domain of is
.
2: .
3: -intercept is
and
-intercept is
.
4: Vertical asymptote .
Hole at .
5: Horizontal asymptote is at , not intersected.
6:
\Interval | \ \
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Number chosen \ | \
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Value of | \
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Location of graph \ | \
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\ Above \ | \
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Below | \
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Below | \
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Above | \
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Point of graph \ | \
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7 and 8:
\The graph of :
.