Limit of as
The limit of as is .
How to work it out
- 1
We want what x / exp(x) approaches as x β β.
- 2
Direct substitution gives an indeterminate form: β/β. It does not tell us the limit.
- 3
L'HΓ΄pital's rule: when the form is β/β, the limit equals the limit of the ratio of the derivatives.
- 4
Method: exponentials beat powers: L'HΓ΄pital gives 1/eΛ£ β 0.
- 5
Result:
LaTeX source of the formulas on this page
\[ \lim_{x \to \infty} \frac{x}{e^{x}} = 0 \]
\[ \lim_{x \to \infty} \frac{x}{e^{x}} \]
\[ \lim \frac{x}{e^{x}} = \lim \frac{1}{e^{x}} \]Values of x / exp(x) as x β β (computed)
| x | f(x) | Distance from the limit |
|---|---|---|
| 10 | 0.00045399930 | 4.54e-4 |
| 100 | 3.7200760e-42 | 3.72e-42 |
| 1000 | 0.0000000 | 0.00e+0 |
| 10000 | 0.0000000 | 0.00e+0 |
| 100000 | 0.0000000 | 0.00e+0 |
| 1000000 | 0.0000000 | 0.00e+0 |
Questions
What is the limit of x / exp(x) as x approaches β?
The limit of as is .
Which form is it?
β/β.