Guide Vert Chevaux

RTL: Feu vert pour tous les chevaux belges en vue du concours de saut d'obstacles par équipe

Guide Vert Chevaux 1

Feu vert pour tous les chevaux belges en vue du concours de saut d'obstacles par équipe

Guide Vert Chevaux 2

lexpress: Importation de nouveaux chevaux: la MTCSL obtient le feu vert de la HRD

Importation de nouveaux chevaux: la MTCSL obtient le feu vert de la HRD

According to texdoc symbols: \mvert and \mid are identical and produce a relation. \vert is a synonym for | and both produce the same symbol, but should be used in the context of an ordinal, and should be used as an operator, not as a delimiter (p54, bottom). \divides once again produces the same symbol but should be used as a binary “divides” operator. \lvert and \rvert are left and right ...

As you can see, the top formula has \vert size as default. I want the latter formula, How do I change my command? I can't use the \left and \right command because there is no left or right in \vert. Any help is appreciated.

Guide Vert Chevaux 6

How can I change the size of \vert accordingly like \left and ... - TeX

In short, \bigl\vert \bigr\vert is definitely better than \big\vert \big\vert, typographically speaking, as it produces the correct spacing in all cases. A final remark, prompted by a comment from barbara beeton: For the code examples used here, it's not necessary to increase the size of the vertical bars.
Guide Vert Chevaux 8

math mode - Use \big\vert f (x) \big\vert or `\big\lvert f (x) \big ...

Guide Vert Chevaux 9