(1-1/n)^n 1/e

5 min read Jun 16, 2024
(1-1/n)^n 1/e

Exploring the Limit of (1-1/n)^n as n Approaches Infinity

The expression (1 - 1/n)^n holds a special place in mathematics, as its limit as n approaches infinity is surprisingly connected to the fundamental constant e. This article delves into understanding why this limit equals 1/e.

Understanding the Limit

As n grows increasingly large, the term (1-1/n) becomes increasingly close to 1. However, we're raising this value to the power of n, which is also growing infinitely large. This creates a dynamic where we're essentially taking a value slightly less than 1 and multiplying it by itself an increasingly large number of times.

The question then becomes: does this process converge to a specific value, or does it oscillate wildly? The answer, remarkably, is that it converges to a very specific value: 1/e.

Visualizing the Convergence

One way to visualize this convergence is by plotting the values of (1-1/n)^n for increasing values of n. As n grows, the graph approaches a horizontal line, signifying the limit. This horizontal line corresponds to the value 1/e.

Connection to the Constant 'e'

The connection to the constant 'e' arises from the definition of 'e' itself.

The constant e is often defined as the limit of (1+1/n)^n as n approaches infinity. To see the connection, let's rewrite the expression (1-1/n)^n:

(1-1/n)^n = (1 + (-1/n))^n

Now, notice the similarity to the definition of e. By replacing (-1/n) with (1/n) in the expression above, we get the definition of e. This suggests a close relationship between the two expressions.

Mathematical Proof

A more rigorous proof of the limit involves using the concept of the exponential function. By taking the natural logarithm of both sides of (1 - 1/n)^n and applying L'Hopital's Rule, we can show that the limit of the natural logarithm of this expression approaches -1. Exponentiating both sides then gives us the final result:

lim (n -> ∞) (1-1/n)^n = 1/e

Significance of the Limit

This limit has applications in various fields, including:

  • Probability and Statistics: The expression (1-1/n)^n appears in probability calculations related to events occurring with a certain probability in independent trials.
  • Compound Interest: The limit is closely tied to the concept of continuous compounding in finance.
  • Calculus and Analysis: The limit is a classic example of a convergent sequence and provides insights into the behavior of functions as their inputs approach infinity.

Conclusion

The limit of (1 - 1/n)^n as n approaches infinity being equal to 1/e showcases a fascinating connection between the exponential function, the constant 'e', and a seemingly simple expression. This limit highlights the power of mathematical analysis to unveil unexpected relationships and reveal profound insights.

Featured Posts