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Example Questions
Example Question #1 : Find Intercepts And Asymptotes
Suppose the function below has an oblique (i.e. slant asymptote) at .
If we are given , what can we say about the relation between and and between and ?
We can only have an oblique asymptote if the degree of the numerator is one more than the degree of the denominator. This stipulates that must equal .
The slope of the asymptote is determined by the ratio of the leading terms, which means the ratio of to must be 3 to 1. The actual numbers are not important.
Finally, since the value of is at least three, we know there is no intercept to our oblique asymptote.
Example Question #51 : Polynomial Functions
Find the -intercept and asymptote, if possible.
To find the y-intercept of , simply substitute and solve for .
The y-intercept is 1.
The numerator, , can be simplified by factoring it into two binomials.
There is a removable discontinuity at , but there are no asymptotes at since the terms can be canceled.
The correct answer is:
Example Question #2 : Find Intercepts And Asymptotes
Find the -intercepts of the rational function
.
The -intercept(s) is/are the root(s) of the numerator of the rational functions.
In this case, the numerator is .
Using the quadratic formula,
the roots are .
Thus, are the -intercepts.
Example Question #53 : Polynomial Functions
Find the vertical asymptotes of the following rational function.
No vertical asymptotes.
Finding the vertical asymptotes of the rational function amounts to finding the roots of the denominator, .
It is easy to check, using the quadratic formula,
that the roots, and thus the asymptotes, are .
Example Question #54 : Polynomial Functions
Find the y-intercept and asymptote, respectively, of the following function, if possible.
Before we start to simplify the problem, it is crucial to immediately identify the domain of this function .
The denominator cannot be zero, since it is undefined to divide numbers by this value. After simplification, the equation is:
The domain is and there is a hole at since there is a removable discontinuity. There are no asymptotes.
Since it's not possible to substitute into the original equation, the y-intercept also does not exist.
Therefore, the correct answer is:
Example Question #1 : Find Intercepts And Asymptotes
What is a vertical asymptote of the following function?
To find the vertical asymptote of a function, we set the denominator equal to .
With our function, we complete this process.
The denominator is , so we begin:
Example Question #7 : Find Intercepts And Asymptotes
What is the -intercept of the following function?
There is no -intercept.
The y-intercept of a function is always found by substituting in .
We can go through this process for our function.
Example Question #8 : Find Intercepts And Asymptotes
Which of these functions has a vertical asymptote of and a slant asymptote of ?
In order for the vertical asymptote to be , we need the denominator to be . This gives us three choices of numerators:
If the slant asymptote is , we will be able to divide our numerator by and get with a remainder.
Dividing the first one gives us with no remainder.
Dividing the last one gives us with a remainder.
The middle numerator would give us what we were after, with a remainder of -17.
The answer is
Example Question #1 : Find Intercepts And Asymptotes
Find the zeros and asymptotes for
.
Zero: ; Asymptote:
Zeros: ; Asymptote:
Zero: ; Asymptotes:
Zero: ; Asymptotes:
Zeros: ; Asymptotes:
Zero: ; Asymptote:
To find the information we're looking for, we should factor this equation:
This means that it simplifies to .
When the equation is in the form of a fraction, to find the zero of the function we need to set the numerator equal to zero and solve for the variable.
To find the asymptote of an equation with a fraction we need to set the denominator of the fraction equal to zero and solve for the variable.
Therefore our equation has a zero at -3 and an asymptote at -2.
Example Question #10 : Find Intercepts And Asymptotes
Find the slant and vertical asymptotes for the equation
.
Vertical asymptote: ; Slant asymptote:
Vertical asymptote: ; Slant asymptote:
Vertical asymptote: ; Slant asymptote:
Vertical asymptote: ; Slant asymptote:
Vertical asymptote: ; Slant asymptote:
Vertical asymptote: ; Slant asymptote:
To find the vertical asymptote, just set the denominator equal to 0:
To find the slant asymptote, divide the numerator by the denominator, but ignore any remainder. You can use long division or synthetic division.
The slant asymptote is
.