# Thread: prove , ray of circle inside the square

1. ## prove , ray of circle inside the square

square around the circle :

area of square = 2r^2

area of circle = Pi r^2

area of square / area of circle = pi / 4

area of square based on ray r :

area of square = r^2

Area of circle = 1/4 Pi * r^2

area of square / area of circle => 1r^2 / 1/4 pi r ^ 2 = 4 / pi

find ray dependence from relation area of circle to area of square :

4 / pi * ( pi * r^2 ) = 4 ( area of square around the circle is known = 4 )
4r^2 = 4
x = 1

there is not incorrect, ray is dependence from area of square

2. ## Re: prove , ray of circle inside the square

Well, first of all, the area of the square is not \displaystyle \begin{align*} 2r^2 \end{align*}, it's \displaystyle \begin{align*} (2r)^2 = 4r^2 \end{align*}.