# Pi day Countdown #12 – Pi and the Transcendental Number

Leonhard Euler, considered to be one of the best mathematicians of all time, had the honor of having a few Transcendental numbers named after him. The Euler’s number or 2.718281828459… is not only a beautiful and a powerful number, it also has a very interesting connection with $\pi$.

The Euler’s number $e$ can be expressed in the Euler’s Identity as:

$e^{ix} = \sin(x) + i \cos(x)$

and with $x = \pi$ the identity becomes

$e^{i \pi} = \sin(\pi) + i \cos(\pi) = 1$ or $e^{i \pi} -1 = 0$

Which unites some of the most famous mathematical constants, not only just $\pi$. There is also $i$ the number that was so controversial that it was named imaginary as a joke. The number $0$ which represented the concept of nothingness, a concept that wasn’t accepted as a number for millennia. The number $1$ that started it all, and not to forget $\pi$ one of the most famous numbers in mathematics.

PS: For more Pi Day countdown articles, visit the fun corner