Definition:Wallis's Number/Historical Note

Historical Note on Wallis's Number
The cubic $x^3 - 2 x - 5 = 0$ was used by as a example to demonstrate how Newton's Method could be used to solve certain equations numerically.

The real root of this equation has since become known as Wallis's number.

It has subsequently been used as a test for a number of different methods of approximation.

It is known to over $4000$ digits.

Also see

 * Newton's Method/Example/x^3 - 2 x - 5 = 0