# Displaystyle numbers in exponent

In a math equation, I have

$$e^{\dfrac{A+B}{B}}$$


which is simplified as

$$e^{\dfrac{A}{B} + 1}$$


however the "1" is now too small and the equation aspect is not so nice. Is there a way to have a "1" with the same dimensions of "A" and "B" without go back to the "small" \frac?

• I don't like the look of it, but e^{\displaystyle\frac{A}{B} + 1} will get the 1 in \displaystyle. Commented May 25, 2017 at 12:28
• I would write expressions like this as \exp(...) Commented May 25, 2017 at 12:30
• As Martin suggests, $\exp \biggl(\frac{A}{B} + 1\biggr)$ If you are using LaTeX, don't use , but $...$ delimiters or the equation* environment. Commented May 25, 2017 at 12:30
• @StevenB.Segletes No need to use \dfrac after \displaystyle.
– sodd
Commented May 25, 2017 at 12:31
• I agree with both Martin and @StevenB.Segletes. Further, in exponents $a/b$ is usually preferable to $\frac{a}{b}$.
– JPi
Commented May 25, 2017 at 12:37

Don't you think one of these would look nicer?

 \documentclass{article}
\usepackage[utf8]{inputenc}
\usepackage[T1]{fontenc}
\usepackage{amsmath}
\usepackage{lmodern}
\usepackage{slantsc}
\newcommand\textscsl[1]{\textsc{\slshape#1}}

\begin{document}

$e^{ \scriptscriptstyle\frac{A}{B}+ 1} \quad e^{\tfrac{\textscsl{a}}{\raisebox{0.3ex}{\textscsl{\scriptsize b}}} + 1} \quad e^{\tfrac{A}{B} + 1}$%

\end{document}


• \tfrac{}{} is OK! Commented May 25, 2017 at 12:52
• @Mico: I agree that with capital letters in fractions, that may be not the best solution, but generally speaking, I understand it's hard to read a mix of scriptstyle and \scriptscriptstyle in an exponent. Commented May 25, 2017 at 14:11
• @Alby Stalks: I've added a 3rd solution, close o the default, but with a better vertical spacing of the fraction. Commented May 25, 2017 at 15:00

Let's consider various ways to typeset the exponential expression of interest:

• The first form, produced by e^{\dfrac{A}{B} + 1}=e^{{\displaystyle\frac{A}{B}} + 1}, is clearly awful: The "A" and "B" fractional terms are set in text style, but the "+1" term is set in script style.

• In the second form, the \frac and the +1 terms are both set in display style math mode. I think we can all agree that it doesn't look good either: Visually speaking, the exponent term completely and utterly dwarfs the base term ("e").

• The third form uses \textstyle for all material in the exponent. The exponent term still dwarfs the base term, but no longer completely and utterly.

• The fourth form, which is what results if no special math mode directive is issued in the exponent, is starting to take on a somewhat balanced look.

• Observe that the fractional term \frac{A}{B} in the fifth form, which uses \scriptscriptstyle throughout the exponent, has the exact same size as the fractional term in the fourth form. The only difference between the two forms is in the "+1" term, which (to my eyes at least) looks strangely stunted and diminished in the fifth form when compared to the fractional term that precedes it.

• In my view, none of the first five forms are satisfactory. (Well, the fourth form comes close...) You should really consider using either inline fraction notation, as is done in the sixth form, or \exp(...) notation, as is done in the 7th and final form. Your readers will thank you!

\documentclass{article}
\begin{document}
$% start display-style math mode e^{{\displaystyle\frac{A}{B}} + 1} % awful \quad e^{\displaystyle\frac{A}{B}+1} \quad e^{\textstyle\frac{A}{B}+1} \quad e^{\frac{A}{B}+1} % "\scriptstyle" is default math mode \quad e^{\scriptscriptstyle\frac{A}{B}+1} \quad e^{(\mkern-1.5muA/\mkern-2.5mu B+1)} % apply some (negative) kerning \quad \exp\Bigl(\frac{A}{B}+1\Bigr)$
\end{document}

• For my needs the third form is the best. Subsequently, once the formula's development is well introduced it can be passed to the last. This is because many students find it difficult to understand the meaning of the exponent if they do not see it directly in the formula. Commented May 26, 2017 at 14:51