The graph shows a function \(f\) for positive \(x\).
a) From the graph, describe how \(f(x)\) behaves as \(x\) becomes large. Identify the horizontal line around which the graph oscillates, state whether the graph crosses that line, and describe what happens to the height of the oscillations.
b) For \(x>0\), you are also told that
\(2-\frac{8}{x}\le f(x)\le2+\frac{8}{x}\).
Use the Squeeze Theorem to determine \(\lim_{x\to\infty}f(x)\) and the corresponding horizontal asymptote.

Hints
- In part a), use only visible features of the graph: crossings, center line, and changing vertical spread.
- In part b), compare the limits of the supplied lower and upper bounds.
- A finite end limit determines a horizontal asymptote.
Solution
1. The graph oscillates above and below \(y=2\), crosses \(y=2\) repeatedly, and the vertical size of the oscillations decreases as \(x\) increases.
2. As \(x\to\infty\), both \(2-\frac{8}{x}\) and \(2+\frac{8}{x}\) approach \(2\).
3. Since \(f(x)\) stays between those two functions for positive \(x\), the Squeeze Theorem gives \(\lim_{x\to\infty}f(x)=2\).
4. Therefore the horizontal asymptote is \(y=2\).
Answer
a) The graph oscillates above and below \(y=2\), crosses \(y=2\) repeatedly, and its oscillation height shrinks as \(x\) increases.
b) Since \(2-\frac{8}{x}\to2\) and \(2+\frac{8}{x}\to2\), the Squeeze Theorem gives \(\lim_{x\to\infty}f(x)=2\), so the horizontal asymptote is \(y=2\).