\begin{proof}
Let $g_1, g_2 \in G$. Then $\theta(g_1) = Ng_1$ and $\theta(g_2) = Ng_2$. \\
\begin{equation*}
\begin{split}
\text{ Now, } \theta(g_1g_2) &= Ng_1g_2 \\
& = Ng_1 Ng_2 \\
& = \theta(g_1) \theta(g_2)\\
\end{split}
\end{equation*}
$\therefore \theta$ is a group homomorphism. $\theta$ is clearly onto.
\end{proof}
Is there a way to left justify the first line of the equation, but then keep the = signs aligned in the subsequent lines? I've tried many combinations of \begin{align} etc with no luck. (It appears that the \begin{equation} favors center alignment.)
Best Answer
You can do it with
aligned
. I also provide what I firmly believe is a better version.