The code below was created from Mathematica software:
%% AMS-LaTeX Created with the Wolfram Language : www.wolfram.com
\documentclass{article}
\usepackage{amsmath, amssymb, graphics, setspace}
\newcommand{\mathsym}[1]{{}}
\newcommand{\unicode}[1]{{}}
\newcounter{mathematicapage}
\begin{document}
\title{Me Salva! ITD07}
\author{Leandro Carvalho}
\date{21/06/2017}
\maketitle{Estudo}
\begin{doublespace}
\noindent\(\pmb{\text{r1}=\sqrt{18};\text{r2}=6\text{Cos}[\theta ];}\\
\pmb{\text{g1}=\text{PolarPlot}[\text{r1},\{\theta ,0,2 \pi \}];}\\
\pmb{\text{g2}=\text{PolarPlot}[\text{r2},\{\theta ,0,2 \pi \}];}\\
\pmb{\text{Show}[\{\text{g1},\text{g2}\}]}\\
\pmb{}\\
\pmb{\text{RegionPlot}\left[x^2+y^2<18,\{x,0,10\},\{y,0,10\},\text{PlotStyle}\to \text{Yellow}\right]}\\
\pmb{\text{RegionPlot}\left[(x-3)^2+y^2<9,\{x,0,10\},\{y,0,10\},\text{PlotStyle}\to \text{Blue}\right]}\\
\pmb{\text{RegionPlot}\left[x^2+y^2<18\&\&(x-3)^2+y^2<9,\{x,0,10\},\{y,0,10\}\right]}\\
\pmb{}\\
\pmb{\mathcal{R}=\text{ImplicitRegion}\left[x^2+y^2<18\&\&(x-3)^2+y^2<9,\{x,y\}\right];}\\
\pmb{\text{RegionDimension}[\mathcal{R}]}\)
\end{doublespace}
\begin{doublespace}
\noindent\(2\)
\end{doublespace}
\begin{doublespace}
\noindent\(\pmb{\int _0^{\frac{\pi }{4}}\int _0^{\sqrt{18}}5 r^3 \text{Sin}[\theta ] \text{Cos}[\theta ]drd\theta +\int _{\frac{\pi }{4}}^{\frac{\pi
}{2}}\int _0^{6 \text{Cos}[\theta ]}5 r^3 \text{Sin}[\theta ] \text{Cos}[\theta ]drd\theta }\)
\end{doublespace}
\begin{doublespace}
\noindent\(135\)
\end{doublespace}
\end{document}
The pmb and noindent commands are for what?



\pmbisPoor Man's Bold, for fonts which do not have a bold version (usually bold version of math symbols, viz a bold version of\mathbb.\noindentsuppresses the indentation of the next paragraph. – Bernard Jun 21 '17 at 16:29