Mathematical constant e is the basis of natural logarithmic function. Sometimes called Euler number, named after the Swiss mathematician Euler; There is also a relatively rare name Napier constant to commemorate the introduction of logarithm by Scottish mathematician John Napier. Its value is about:

e ≈ 2.7 1828

Just like pi and imaginary units I and E are one of the most important constants in mathematics.

lim( 1+ 1/x)^x =e

X→ infinity

E is a constant value (irrational number), and e is approximately equal to 2.7 182 1828.

E is the base of natural logarithm: lnx=loge(x)

E is born by solving the differential equation of dy/dx =1/X.

Because there happens to be a derivative of log (e)x equal to1/x.