This publication 'the golden square', describes how the number Pi is in the square. And with this number Pi (square PI number) I show a third way how to determine the circumference of a circle.
4) the pyramid Pi method.
5) the pentagram Pi method.
6) the square Pi method.
There are now three unique geometrically based Pi numbers, which are unmatchable.
In addition, I show that from the square every angle on the circle can be determined (without protractor) that are equal to each other.
Everything in this publication is new and unknown in mathematics.
What mathematical science has failed to explain in thousands of years is revealed in my publications today.