Hello,
in that case, code would not help understanding, only the image can help to understand, the images represent 3 Intervals. And as you may see, in the 3 one the size of character "[" does not match the size of the expression with pi/2.
the "[" is smaller it does not adapt to the expression between "[" and "]" ... this is what I try to solve, not more.
When I have "[pi/2, pi/2]" "close/ close" the size ôf brackets adapt to the expression
When I have "]pi/2, pi/2 ]" open/close" the size of brackets adapt to the expression
When I have "[pi/2, pi/2[" close/open or "]pi/2,pi/2[" open, open, the size of the second bracket DOES NOT adapt. In other words, when I input and interval, the second bracket does not adapat the size of expression when it is open.