Is there a way to simplify the following expression: 


$\lgroup{\int^A\_0 x(s)ds}\rgroup ^2$


I'm looking for an expression that can possibly get rid of the squared term, so that I can have just an integral of the first order.



Expressions for the Square of an Integral
I'm not sure about simplifying, but you can easily write your objective functional in Bolza form like this:


$$
\begin{align}
&\min\_{u(t) \in \Omega(t)} \, J = z(T)^2 + \int\_{0}^{T} s(t)u(t)dt \\
s.t. &\frac{dz(t)}{dt} = r(t)u(t),\quad z(0) = 0 
\end{align}
$$


