# Contionous points

Printable View

• December 21st 2013, 04:12 AM
davidciprut
Contionous points
I explained the question in the picture.
By the way, The question ask to find all continuous points. What is that mean to be continous at a point?
• December 21st 2013, 04:42 AM
romsek
Re: Contionous points
Quote:

Originally Posted by davidciprut
I explained the question in the picture.
By the way, The question ask to find all continuous points. What is that mean to be continous at a point?

continuity of f at a point x means

$f(x)=\displaystyle{\lim_{t\to x}}f(t)$

other than using the word intensity where I think you mean density this looks correct.
There is an irrational number in any delta neighborhood of every rational no matter how small and vice versa.
So D has no limit at any of the rational or irrational numbers and thus is continuous nowhere.