# How can I make the size of an integral sign even larger than the 'standard large integral' size?

I would to syntax an integral that is even larger than $${\Large\int} _{x_0}^{x_0+L}$$ with the standard integral size shown for reference:$${\int} _{x_0}^{x_0+L}$$

As unfortunately, I cannot get this to work with this site.

Does anyone know if there exists such a way to code a very large integral? My reasons for asking is because the integrand is very large due to fractions in the exponentials.

Kindest Regards

Thank You,

Blaze

## EDIT:

Just thought I would mention that now I have been given answers to my question, I can clearly see that this sort of formatting is most disagreeable with the majority of users. Comments indicate that using exp instead of $e^{x}$ is a much better way to format when the argument of the exponent contains fractions.

I completely agree with this now, so thanks to those of you who pointed this out to me.

• en.wikibooks.org/wiki/LaTeX/Fonts#Sizing_text – Will Jagy Sep 16 '15 at 2:03
• $$\verb/ large/ \large\int_{a}^b,\quad \verb/ Large/ \Large\int_{a}^b\quad \text{ and } \verb/ Huge/ \Huge\int_{a}^b ???$$ – achille hui Sep 16 '15 at 2:33
• Considering that this is what you wanted to use it for, it would have been better not to bother. What is the purpose of those excessively large integral sign in your question? – mrf Sep 16 '15 at 4:44
• The result on the page @mrf linked to is horrible. I seem to remember that Knuth explained somewhere unambiguously why modifying the standard formatting in LaTeX was almost always a bad idea. In the present case, $$\int_{x_0}^{x_0+L}\mathrm{e}^{-2\pi i r x/L}\mathrm{e}^{2\pi i p x/L}\mathrm{d}x$$ is much better. – Did Sep 16 '15 at 5:59
• Or perhaps $$\int_{x_0}^{x_0+L} \exp(-2\pi i rx/L)\exp(2\pi i px/L)\,dx$$ (possibly with two-story fractions if you insist) – mrf Sep 16 '15 at 6:02
• @mrf Now that definitely looks better I admit that, I would never have thought to use exp instead, I live and learn. – BLAZE Sep 16 '15 at 6:09
• I never got a downvote for properly formatting my posts (or was not aware of the fact). As explained on this page, there are ways to deal with too small exponents (inlined fractions, always, and, in the present case, inlined exponential function). – Did Sep 16 '15 at 6:15

To make just the integral sign bigger, but leave the limits alone, we can define a new operator with \operatorname{\Huge\int}: $$\operatorname{\Huge\int}_0^1x\,\mathrm{d}x=\frac12$$ Unfortunately, the integral sign is thicker than with the bigints package.

The same can be done for summation with \operatorname*{\Huge\sum}: $$\operatorname*{\Huge\sum}_{k=1}^\infty\frac1{k^2}$$ The asterisk after \operatorname puts the limits above and below the operator.

• I have added \operatorname* to the MathJax Tutorial. – robjohn Sep 16 '15 at 3:09
• The huge sum makes the $\infty$ look tiny in comparison. What's the cardinality of $\displaystyle\Huge\sum$, then? – Asaf Karagila Sep 18 '15 at 14:25

Don't forget you can just make the whole expression big rather than individual pieces: e.g. just putting \Large out front gives

$$\Large \int_{x_0}^{x_0+L}\mathrm{e}^{-\frac{2\pi i r x}{L}}\mathrm{e}^{\frac{2\pi i p x}{L}}\mathrm{d}x =\begin{cases}L & \space \mathrm{for} \space r=p,\\0&\ \mathrm{for}\space r\ne p \end{cases}$$

If you want to enlarge the MathJax displayed on this site for yuorself (rather than for everyone) you can right-click on an equation, go to Math Settings > Scale All Math ... and entering a percentage. I currently use 115% MathJax magnification here on Math.SE.

• Unless you are visually impaired or otherwise dependent on larger rendering, you should weigh this against that most other SE users will not see the equations (you type) at the same size, so you might end up using Markup wich is hard to read on 100%. – AlexR Sep 18 '15 at 16:18
• If those users can't see the equations, perhaps this suggestion will help them. I'm not sure what you're getting at. I'm also having trouble parsing the last part of your comment: "so you might end up using Markup wich is hard to read on 100%." Could you rephrase it to clarify? – Antonio Vargas Sep 18 '15 at 16:43
• I mean that equations you set may look allright on your screen (115%) and be hard to read on default magnification :) – AlexR Sep 18 '15 at 17:22
• As Did mentioned, Knuth recommends not to modify standard formatting, and if people are careful about exponents of exponents and the like then I really don't think there will be a problem. – Antonio Vargas Sep 18 '15 at 17:51