How to have different mesh densities on a simple, 1D geometry?

Hi. This may be a very obvious question, but I can't seem to be able to find the solution.

I have a very simple 1D geometry: a line segment from 1 to 7 i.e. 1<x<7.

I want to have an extremely fine user controlled mesh for 1<x<2.25, and a much coarser mesh for 2.25<x<7. How do I do this? I assume it is easy and that I'm just missing the obvious. If there isn't an obvious way of doing it, I can reply here with that I've tried already.

Thanks.