Exponential Asymptotes 68984C
1. **State the problem:** We are given the function $f(x) = -5^x$ and asked to find its vertical and horizontal asymptotes.
2. **Recall the definitions:**
- A **vertical asymptote** occurs where the function approaches infinity or negative infinity as $x$ approaches a certain value.
- A **horizontal asymptote** is a horizontal line that the graph approaches as $x$ goes to $+\infty$ or $-\infty$.
3. **Analyze the function:**
- The function is $f(x) = -5^x$, which is an exponential function with base 5 and a negative sign.
- Exponential functions of the form $a^x$ with $a>1$ have no vertical asymptotes because they are defined for all real $x$.
4. **Vertical asymptotes:**
- Since $f(x)$ is defined for all real $x$, there are no vertical asymptotes.
5. **Horizontal asymptotes:**
- As $x \to +\infty$, $5^x \to +\infty$, so $f(x) = -5^x \to -\infty$.
- As $x \to -\infty$, $5^x \to 0^+$, so $f(x) = -5^x \to 0^-$.
- Therefore, the horizontal asymptote is the line $y=0$.
**Final answer:**
- Vertical asymptotes: None
- Horizontal asymptote: $y=0$