who discovered pi and formula of Circumference?

The value of pi is most important in modern science as well as mathematics.

The value of pi using everywhere small unit measure of electron and a large unit of galaxies planets as well as the whole universe.

In mathematics, pi is most useful in the circle in geometry 

we can't imagine mathematics without pi.

 To find volume and area of circular object need pi.

Aryabhatta already had discovered the value of pi.

चतुरधिकं शतमष्टगुणं द्वाषष्टिस्तथा सहस्राणाम् । श्रप्रयुतद्वयविष्कम्भ स्यासन्नो वृत्तपरिणाहः   (आर्यभटीय गणितपाद श्लोक १०)

It means

Add four in hundred, then multiply by eight and add sixty-two thousand. 

It's the value of Circumference which has twenty thousand diameters.

Its is clearly told that 

Circumference = ((100+4)*8)+62000 = 62832

we know the formula  Circumference = 2πr      ( r= d/2)

             

                    or,    62832 = 2*π*20000/2

                    or,          π = 62832/20000

                     or,         π = 3.1416

which is the 

Approximate Measure of pi

Great Mathematician Aryabhatta was already told about pi,
and also the formula of Circumference 
because there was clearly explained about Circumference and
this measure is fit with the value of pi and formula of Circumference

what do you think comment below

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