Hi Stefan,
Since I am not so fluent with these tools and procedures I've sent to your mail address: [email protected] pdfs of two pages (from the book I'm translating):

1) Page 87_brackets bat.pdf : original coding with in the first halfh of coded line

2) Page 87_brackets OK.pdf: where I've replaced and the brackets of first halh appear bigger, as those in the second half.

As I say on the mentioned mail, I have to keep on my work of translation, therefore I feel better from now on to use commands instead.

Again, I thank you so much for your invaluable support and I look fordward to account for your help.
Kind regards,
Jon

Hi Jon,

when you write a post, there's an "Attachments" tab/link below the edit field. There you can add images or PDF attachments or .log files.

In the PDF files, I can see that you use a non-default font with different glyph sizes. Looks like the | symbol is smaller than with the default font, that's why the automatic sizing (with a small alpha) makes it smaller, and with the (bigger) beta it get's bigger. In my test with the standard font, the | symbol was already so big that LaTeX does the larger sizing. So it would have been clearer from the beginning with a PDF or a screenshot of the formula or, in the best case, with a complete small LaTeX document ( minimal working example ) that would show it. The small piece of code did not show the font.

Also, before I saw the sizing with the font in the PDF, I thought you saw a problem with the \left and \right sizing. There's just no problem, it adjusts to the content between \left and \right. Then I understood that you meant that different \left and \right groups have a different height, but that's normal, as they adjust to their inner content and not to other terms outside. To have the same result with different \left and \right pairs, you can insert some larger content from the other formula as size reference by \vphantom{\beta_u} that adds an invisible vertical space of that size. Or choose \big or \bigg, right. It's not the automatic sizing of \left and \right to their content, but of the braces or brackets of different formula parts. This shows it a bit more visible, you want the braces on the left side like on the right side of the relation symbol, no matter what the left side height is: