# Handwriting: distinguishing between upper and lowercase “x”.

I'm following along with Kreyszig's intro to functional analysis text, where he uses $$X$$ to indicate an abstract set, and often uses $$x$$ to indicate an element of $$X$$. I want to match his notation, but in a way that--when handwritten--makes a clear distinction between the upper and lower case letters. My normal lowercase $$x$$ is more curvy, but I feel like that's not enough, and adding serifs by hand for the big $$X$$ is too cumbersome. I did see a professor that just swiped a line across the top of an x-shape to indicate the big $$X$$ but that looked sloppy to me. Maybe I'm just being too anal about it, but I like my math writing to look good. Any suggestions?

I threw the functional-analysis tag on here because this is the context in which my question seems most relevant.

Edit: Consider that the cartesian product symbol $$\times$$ causes some interference as well.

• You could also make the top angle in "X" smaller. – Alberto Takase Feb 4 at 9:28