1. Introduction
This article introduces Euler's formula.
Two, content
Three, to prove
Use the Taylor series to expand separately, and then put them together. If the sign is found to be wrong, introduce the imaginary number i, just make it together.
Four, summary
Euler's formula is known as the most beautiful mathematical formula, the main reason is that it combines Euler's number e, imaginary number i, trigonometric functions and π together.