What is the relationship of pi?

Answer 1

'pi' in IRRATIONAL number. This means that its decimal points go to infinity and there is NO regular order in the decimal digits.

You will be given 'pi' = 3.14, or 3.1416, or 22/7 when learning circle calculations. However, these are only approximations.

In circle calculations 'pi' has the relationship;-

Circumference equals two multiplied to 'pi' multiplied to the radius.

Algebraically written as ;-

C = 2pir

or

C = pi*d ( where 'd' is the diameter).

Remember two radii equals one diameter. ( 2r = d )

The other circle equation to learn is are of a circle.

Area equals 'pi' multiplied to the radius squared.

Algebraically

A = pi* r^(2)

'pi' has been known from ancient times. It was noticed that when a mule/donkey was driven round a well , on a tether, to bring up water. The tether was the radius. and the track made by the mule was the circumference. It was noticed that however, long or short the tether, and thereby the circumference of the circle. They always had a relationship.

Circumference is directly proportional to the radius.

C directly proportional r

To equate this a constant 'k' is inserted.

C = k*r

Algebraically rearranging

k = C/r It was noticed that 'k' was ALWAYS the same for any circle however large or small. So it was given the name 'pi' from the Classical Greek small case letter 'p' , for proportionality, which is 'pi'

pi = 3.1415927..... is an IRRATIONAL number, which means the decimals digits go to infinity and there is no regular order in the decimal numbers.

However, when learning circles you are given pi = 3.14, or 3.1416, or 22/7 , but remember these are only Approximations. .

Supa Dupa Computers have calculated 'pi' to at least 50 billion places and still going.

Hope that helps!!!!!

Answer 2

circumference of of circle / Radius of the circle