We are given a graph of a function and asked to find information about the reciprocal of this function. Specifically, we need to determine the asymptotes, intervals of increase and decrease, max/min points and four other points, and a sketch of the reciprocal function.
2025/4/23
1. Problem Description
We are given a graph of a function and asked to find information about the reciprocal of this function. Specifically, we need to determine the asymptotes, intervals of increase and decrease, max/min points and four other points, and a sketch of the reciprocal function.
2. Solution Steps
First, let's analyze the given graph. It looks like a parabola with a vertex at . Thus, the equation of the given graph is .
Now we want to consider the reciprocal function, .
a) Asymptotes:
The denominator of is .
Since is always positive and never equal to 0, there is no vertical asymptote.
As approaches infinity, approaches
0. Therefore, there is a horizontal asymptote at $y = 0$.
b) Intervals of increase and decrease:
To find the intervals of increase and decrease, we can analyze the derivative of .
If , then the function is increasing.
If , then the function is decreasing.
when , which means . So, the function is increasing when .
when , which means . So, the function is decreasing when .
Thus, the function is increasing on the interval and decreasing on the interval .
c) State max/min points and four other points:
Since the function is increasing for and decreasing for , there is a maximum at .
The value of the function at is . Therefore, there is a maximum point at .
Four other points:
so .
so .
so .
so .
d) Sketch the reciprocal function:
The reciprocal function has a horizontal asymptote at . It is increasing for and decreasing for . The maximum value is at . We also have the points and and and .
3. Final Answer
a) Asymptotes: horizontal asymptote at . No vertical asymptotes.
b) Intervals of increase and decrease: increasing on , decreasing on .
c) Max/min points and four other points: Maximum at , , , , .
d) Sketch: The graph starts close to for large negative , increases to a maximum of 1 at , then decreases back towards for large positive .