I am trying to put the bar on the variable but I either get it on the argument with \bar command or over the whole with \overline. The expression is. Look especially at the derivative and s:
\begin{align*}
\frac{d\bar{x_{1}(\tau)}}{d\tau}=\quad&\bar{x_{1}}\left[\bar{r_{1}}\left(1-\bar{x_{1}}-\bar{\eta_{12}}\bar{x_{2}}-\bar{\eta_{13}}\bar{x_{3}}-\bar{\eta_{14}}\bar{x_{4}}\right)-\bar{f_{11}}\bar{y_{1}}-\bar{f_{12}}\bar{y_{2}} \right] +\bar{s_{i}(\tau)},\quad \bar{x_{1}(0)}>0\\
\end{align*}
\bar{x}_{1}(\tau)instead of\bar{x_{1}(\tau)}?? – David Carlisle Dec 20 '19 at 19:43\bar{x}_1rather than\bar{x_1})? – Werner Dec 20 '19 at 19:46\baris pushes slightly to the right since math variables are set with a slant. – Werner Dec 20 '19 at 20:07x_{1}{\tau)construct inside the argument of\bar? – David Carlisle Dec 20 '19 at 20:19x_{1}{\tau)not justxas the argument if you have not yet typed either and have just typed\bar??? – David Carlisle Dec 20 '19 at 21:06