mjhjmtu

How can I give one line in LaTeX more vertical height so that something like

$fracn^n2^2n * n^n^2$

displays correctly? I mean, how to give the 2 term more vertical displacement, so that it looks like it's above the top n in the term n^n^2 in the denominator?

Note that increasing line spacing doesn't work because LaTeX does not fill the space with the characters. (When I searched for this ability, this was all that came up.)

I think the denominator of your frac expression suffers from two issues:

• a "cramped" look, i.e., the exponents are not raised much above the baseline


• first- and second-order exponents are raised to (very nearly) the same height

How to remedy these issues?

• To address the first issue, switch to "uncramped" mode -- see the ufrac macro below.



• 
  

  To remedy the second issue, I suggest you switch from n^n^2 to n^n^2. (The two forms are the same, mathematically speaking, but they are quite differnt from a typographic point of view.) That, or use parentheses to visually "enclose" the n^n term.

  
  
  

  Alternatively, consider switching from "standard" frac notation to inline-fraction notation.

  
  

Whatever else you do, please don't use the unnecessary * multiplication symbol. If you can't do without an explicit multiplication symbol, do use cdot, not *.

documentclassarticle

%% "uncramped" frac macro:
%% (Source: @egreg [who else?!], https://tex.stackexchange.com/a/337334/5001)
makeatletter
newcommandufrac[2]% 
 frac#1mathpaletteufrac@den#2
newcommandufrac@den[2]#1#2
makeatother

begindocument
inline math mode, verb+frac+ notation

$fracn^n2^2n * n^n^2 % OP's expression
 quad
 ufracn^n2^2n n^n^2 
 quad
 ufracn^n2^2n (n^n)^2$ 

bigskip
display math mode, verb+frac+ notation

smallskip
$displaystyle 
 fracn^n2^2n n^n^2
 quad
 ufracn^n2^2n n^n^2 
 quad
 ufracn^n2^2n (n^n)^2$

bigskip
inline-frac notation

smallskip
$n^n/(2^2n n^n^2) 
 quad
 n^n/(2^2n (n^n)^2)$ 
enddocument

Does this go in the right direction?

documentclass[fleqn]article

begindocument
paragraphOriginal:
$fracn^n2^2n * n^n^2$
[fracn^n2^2n * n^n^2]

paragraphProposal:
$fracn^n2^2n * mathstrut n^n^2$
[fracn^n2^2n * mathstrut n^n^2]


paragraphWith brackets:
$fracn^n2^2n * ( n^n)^2$

[fracn^n2^2n * (n^n)^2]

enddocument