Code: Select all
\documentclass[fleqn]{article}
\usepackage{enumitem}
\usepackage{fullpage}
\usepackage[margin=1in]{geometry}
\usepackage{graphicx}
\usepackage{amsmath}
\usepackage{siunitx}
\usepackage{amstext}
\usepackage[makeroom]{cancel}
\pagestyle{empty}
\setlength{\mathindent}{0pt}
\setenumerate[2]{label=\alph*),leftmargin=0.5cm,itemsep=0pt,topsep=-0.5cm}
\setenumerate[1]{label=\arabic*.,leftmargin=0cm}
\renewcommand{\labelenumi}{\Roman{enumi}.}
\renewcommand{\labelenumii}{\Roman{enumi}. \alph{enumii}}
\allowdisplaybreaks
\begin{document}
\begin{enumerate}
\item
$\begin{aligned}[t]
y(x,t)=0.015\sin(25x-1200t)
\end{aligned}$
\begin{enumerate}
\item
$\begin{aligned}[t]
y(x,t)=0.015\sin(25x+1200t)
\end{aligned}$
\item
\begin{minipage}[t]{2in}
$\begin{aligned}[t]
v=\lambda f
\end{aligned}$
\begin{align*}
\begin{minipage}[t]{1in}
$\begin{aligned}[t]
k&=\dfrac{2\pi}{\lambda} \\
\lambda k&=2\pi \\
\lambda&=\dfrac{2\pi}{k} \\
\lambda&=\dfrac{2\pi}{25} \\
\lambda&=0.25
\end{aligned}$
\end{minipage}
\begin{aligned}[t]
\omega&=2\pi f \\
\dfrac{\omega}{2\pi}&=f \\
\dfrac{1200}{2\pi}&=f \\
191&=f
\end{aligned}
\end{align*}
\end{minipage}
$\begin{aligned}[t]
v&=(0.25)(191) \\
v&=47.75
\end{aligned}$
\end{enumerate}
\end{enumerate}
\end{document}