hi all!
as i recall the dirichlet fn.
(f(x)=1/q if x is rational and x=p/q (in the lowes term) and f(x)=0 if x is irational.)
is integrable, and (i dont know on what interval) is its integral =0 (i think the improprius integral, on all x in R)
But how to proove it's integrable, and that the integral is zero?!?
thanx,
emil
|
|
![[parent]](http://images.planetmath.org:8080/images/uparrow.png)