I would like to know how to scale the size of the text on the integral limits and also the powers in the code given below:
I used the command \DeclareMathSizes{10.95}{10}{7}{7} given here but there was no change to the fonts. Thanks for your help!
Code
\documentclass{article}
\usepackage[landscape]{geometry}
\usepackage{url}
\usepackage{multicol}
\usepackage{amsmath,amssymb,amsthm}
\usepackage{esint}
\usepackage{amsfonts}
\usepackage{blox}
\usepackage{tikz}
\usetikzlibrary{quotes, decorations.pathmorphing, shapes, arrows.meta}
\usepackage{colortbl}
\usepackage{xcolor}
\usepackage{mathtools}
\usepackage{enumitem}
\makeatletter
\newcommand*\bigcdot{\mathpalette\bigcdot@{.5}}
\newcommand*\bigcdot@[2]{\mathbin{\vcenter{\hbox{\scalebox{#2}{$\m@th#1\bullet$}}}}}
\makeatother
%======================================================================================
% FONTS
%======================================================================================
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
% Font
%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%
\RequirePackage{fontspec}
\defaultfontfeatures{Ligatures=TeX}
% For source code
\setmonofont{Source Code Pro Light}[
BoldFont=Source Code Pro,
]
% Normal font
\setsansfont{Fira Sans Light}[
Numbers=OldStyle,
BoldFont=Fira Sans Medium,
ItalicFont=Fira Sans Light Italic,
BoldItalicFont=Fira Sans Medium Italic
]
% Normal font
\setmainfont{Fira Sans Light}[
Numbers=OldStyle,
BoldFont=Fira Sans Medium,
ItalicFont=Fira Sans Light Italic,
BoldItalicFont=Fira Sans Medium Italic
]
\advance\topmargin-1in
\advance\textheight3in
\advance\textwidth3in
\advance\oddsidemargin-1.5in
\advance\evensidemargin-1.5in
\parindent0pt
\parskip2pt
\newcommand{\hr}{\centerline{\rule{3.5in}{1pt}}}
%\colorbox[HTML]{e4e4e4}{\makebox[\textwidth-2\fboxsep][l]{texto}
\begin{document}
{\textbf{Communications Systems}}\\
Z23367851
\begin{multicols*}{3}
\tikzstyle{mybox} = [draw=black, fill=white, very thick, font=\tiny,
rectangle, rounded corners, inner sep=10pt, inner ysep=10pt]
\tikzstyle{fancytitle} =[fill=black, text=white, font=\scriptsize\bfseries]
%------------ Bandwidth and Noise ---------------
\begin{tikzpicture}
\node [mybox] (box){%
\begin{minipage}{0.3\textwidth}
A band limited signal cannot be time limited and a time-limited signal cannot be band limited.\\
\end{minipage}
};
%------------ Bandwidth and Noise Header ---------------------
\node[fancytitle, right=10pt] at (box.north west) {Bandwidth and Noise};
\end{tikzpicture}
%------------ Energy ---------------
\begin{tikzpicture}
\node [mybox] (box){%
\begin{minipage}{0.3\textwidth}
Energy $E = \int\limits_{\infty}^{-\infty}|x(t)|^{2}dt$ if $E$ is finite\\
Power $P=\lim\limits_{T \to \infty}\frac{1}{T}\int\limits_{T/2}^{-T/2}|x(t)|^{2}dt$
\end{minipage}
};
%------------ Energy Header ---------------------
\node[fancytitle, right=10pt] at (box.north west) {Energy};
\end{tikzpicture}
\end{multicols*}
\end{document}



font=\tinywhen setting up\tikzstyle. The text mode command\tinycorresponds to the math mode command\scriptscriptstyle-- that's the smallest there is. Hence, the superscript- and subscript-position symbols can't be made any smaller. Question: What's the purpose of thefont=\tinyoption? – Mico Jul 09 '18 at 17:23\tinyis issued under the default class option10pt. Maybe you could try\DeclareMathSizes{5}{5}{4}{3}, provided that the math font is scalable, but this will no doubt make the text/math unreadable. – Ruixi Zhang Jul 09 '18 at 17:27