# Cosine fixpoint

• May 23rd 2009, 07:28 AM
espen180
Cosine fixpoint
Is the cosine fixpoint (the solution to the equation $x=\cos x$) rational or irrational, and is it possible to prove it?
• May 25th 2009, 01:01 AM
Is the cosine fixpoint (the solution to the equation $x=\cos x$) rational or irrational, and is it possible to prove it?