1. **State the problem:** Determine if the infinite series $$\sum_{n=1}^\infty \frac{5n}{5n + 4n^{-10000}}$$ converges.
2. **Simplify the general term:** The term inside the sum is $$\frac{5n}{5n + 4n^{-10000}}$$.
3. **Rewrite the denominator:** $$5n + 4n^{-10000} = 5n + \frac{4}{n^{10000}}$$.
4. **Divide numerator and denominator by $n$ to analyze behavior as $n \to \infty$:**
$$\frac{5n}{5n + 4n^{-10000}} = \frac{5n}{5n + 4n^{-10000}} \cdot \frac{\cancel{\frac{1}{n}}}{\cancel{\frac{1}{n}}} = \frac{5}{5 + 4n^{-10001}}$$
5. **Evaluate the limit of the term as $n \to \infty$:**
Since $n^{-10001} \to 0$,
$$\lim_{n \to \infty} \frac{5}{5 + 4n^{-10001}} = \frac{5}{5 + 0} = 1$$
6. **Apply the Divergence Test:**
If the limit of the terms of a series does not approach zero, the series diverges.
Here, the limit is 1, not zero.
7. **Conclusion:**
The series $$\sum_{n=1}^\infty \frac{5n}{5n + 4n^{-10000}}$$ diverges because its terms do not approach zero.
Series Convergence 9E8B8A
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