yayMath
Nov12-04, 11:02 PM
Hi,
I need to prove that f(x) has a fixed point, given that f'(x) >= 2 for all x.
my problem is that I've reached the part in which g(x) = f(x) - x
and g'(x) = f'(x) - 1 and therefore g'(x) >= 1
but now i'm completely stuck. I knwo that I need to use the mean value theorem, but i just dont know where.
thanx.
I need to prove that f(x) has a fixed point, given that f'(x) >= 2 for all x.
my problem is that I've reached the part in which g(x) = f(x) - x
and g'(x) = f'(x) - 1 and therefore g'(x) >= 1
but now i'm completely stuck. I knwo that I need to use the mean value theorem, but i just dont know where.
thanx.