Euler's number (usually denoted e in mathematics) is a transcendental constant approximately equal to 2.718281828. It is the base of natural logarithms.
The mathematical constant e (wikipedia) can be defined in various equivalent ways:
- the unique positive real number such that the derivative of the function
f(x) = e
x
is always equal toe
x
- the unique positive real number such that the derivative of the function
log
e
x = 1 / x
- the limit as
n
tends to infinity of(1 + 1/n) ^ n
- the sum of the infinite series
1 / n!
asn
goes from zero to infinity
Ths first of these accounts for the frequency with which e
crops up in models involving compounded growth.