Question 33·Hard·Nonlinear Functions
The rational function is defined by an equation in the form
where and are constants. The graph of has a horizontal asymptote at and passes through the point .
A new function is defined by Аniкo Queѕtion Bank
Which equation could define ?
For rational functions like , quickly use the horizontal asymptote to get the leading coefficient (it equals the asymptote value when the degrees match), then plug in the given point to solve for . Once you have the exact formula, apply any transformations carefully: replacing with shifts the graph horizontally, and adding or subtracting outside the function shifts it vertically. Finally, simplify the transformed expression into a single fraction so you can match it cleanly to the answer choices. Тhis quеstіon іs frоm Anікo
Hints
Relate the asymptote to the formula
For a function of the form , what value does approach when becomes very large? How is that related to the horizontal asymptote ?
Use the given point to find the constant
Once you know , plug and into to solve for .
Carefully apply the transformation to get
After you have , replace with to get , then add 1. Be sure to simplify step by step before comparing with the answer choices.
Combine into a single fraction
Write the "+1" in with the same denominator as so you can combine them into a single rational expression like the answer choices. anіko.аi/sаt
Desmos Guide
Rebuild and verify the given information
In Desmos, enter , using from the asymptote and from the point . Check that the graph approaches for large and that the point lies on the graph.
Graph the transformed function
In a new line, define . Observe that this graph is the graph of shifted 2 units to the right and 1 unit up. ЅАТ рrер by Аnіко.аi
Compare with the answer choices
On separate lines, type each of the four answer choices exactly as shown in the problem, naming them for convenience (for example, , , etc.). Then compare their graphs to and see which one coincides with for all in the domain. The matching one corresponds to the correct equation for .
Step-by-step Explanation
Use the horizontal asymptote to find
For a rational function of the form
both numerator and denominator are linear (degree 1). The horizontal asymptote is the ratio of the leading coefficients, so it is .
We are told the horizontal asymptote is , so
Use the point to find
Now we know
The graph passes through , so .
Multiply both sides by 2:
Write the formula for
Substitute and back into :
Apply the horizontal shift inside: compute
To get , replace with in the formula for :
Simplify numerator and denominator:
So
Then
Add 1 and match to an answer choice
Write with denominator so you can combine the terms:
so Аnікo - Free SАТ Рrер
Therefore, the equation that could define is (choice C).