EN

# JavaScript - e number approximation example

3
points

TheĀ `Math.E`

Ā property returns `e`

Ā mathematical constant (`2.718281828459045...`

).

`e`

Ā is called as Euler's numberĀ or as Napier's constant. However, it was discovered by theĀ Jacob Bernoulli. ItĀ is a mathematical constant used as the base of theĀ natural logarithm.

Using JavaScript it is possible to compute aproximation of `e`

mathematical number in following way.

## 1. Infinity seriesĀ example

To calculate `e`

number folowing function with infinity series can be used - to get better precision infiniteĀ number of iterations with big precision numbers should be used.

```
// ONLINE-RUNNER:browser;
function computeE(iterations) {
var e = 0;
for (var i = 0; i < iterations; ++i) {
var divider = 1;
for (var j = 0; j < i; ++j) {
divider *= (j + 1);
}
e += (1 / divider);
}
return e;
}
console.log( computeE( 1 ) ); // 1
console.log( computeE( 2 ) ); // 2
console.log( computeE( 5 ) ); // 2.708333333333333
console.log( computeE( 10 ) ); // 2.7182815255731922
console.log( computeE( 20 ) ); // 2.7182818284590455
console.log( computeE( 50 ) ); // 2.7182818284590455
```