In article <f15c3684-97b3-4605-a6d0-eb6b8aaf2...@a7g2000prb.googlegroups.com>, Peter Nilsson <ai...@acay.com.au> wrote:
> Keith Thompson <ks...@mib.org> wrote: > > The radian is defined as a ratio of lengths. That ratio > > is the same regardless of the size of the circle. The > > choice of 1/(2*pi) of the circumference isn't arbitrary > > at all; there are sound mathematical reasons for it. > > Yes, but what is pi then? > > > Mathematicians could have chosen to set the full > > circumference to 1, for example, but then a lot of > > computations would contain additional multiplications > > and/or divisions by 2*pi. > > The formula: circumference = 2 x pi x radius is taught > in primary schools, yet it's actually a very difficult > formula to prove! What's to prove? That's the definition of pi. rg -- http://mail.python.org/mailman/listinfo/python-list
