History
It was Johann Bernoulli who noted that
And since
the above equation tells us something about complex logarithms. Bernoulli, however, did not evaluate the integral. Bernoulli's correspondence with Euler (who also knew the above equation) shows that Bernoulli did not fully understand logarithms. Euler also suggested that the complex logarithms can have infinitely many values.
Meanwhile, Roger Cotes, in 1714, discovered that
(where "ln" means natural logarithm, i.e. log with base e). We now know that the above equation is true modulo integer multiples of, but Cotes missed the fact that a complex logarithm can have infinitely many values due to the periodicity of the trigonometric functions.
It was Euler (presumably around 1740) who turned his attention to the exponential function instead of logarithms, and obtained the correct formula now named after him. It was published in 1748, and his proof was based on the infinite series of both sides being equal. Neither of these mathematicians saw the geometrical interpretation of the formula: the view of complex numbers as points in the complex plane arose only some 50 years later (see Caspar Wessel).
Read more about this topic: Euler's Formula
Famous quotes containing the word history:
“Well, for us, in history where goodness is a rare pearl, he who was good almost takes precedence over he who was great.”
—Victor Hugo (18021885)
“There is nothing truer than myth: history, in its attempt to realize myth, distorts it, stops halfway; when history claims to have succeeded this is nothing but humbug and mystification. Everything we dream is realizable. Reality does not have to be: it is simply what it is.”
—Eugène Ionesco (b. 1912)
“English history is all about men liking their fathers, and American history is all about men hating their fathers and trying to burn down everything they ever did.”
—Malcolm Bradbury (b. 1932)