Leonardo Fibonacci was born in Italy in 1175 and he died in 1250.
He lived in Algeria where he began his education with the mathematics. He popularized the Arabic numerals and algebraic notation.
The Fibonacci numbers sequence is a sequence of integers, in which every number is the sum of the previous two. Fibonacci numbers are intimely connected with the golden ratio φ.
Binet’s formula allows to calculate the terms of Fibonacci’s sequence without using the recursion.
We recognize the golden ratio φ and the other root of the equation occurring in this formula :
With these notations, the Binet’s formula becomes :
A short video to learn more (in french) : https://www.youtube.com/watch?v=2f0CVGlYEGQ