Author Topic: Quiz 1-P2  (Read 2794 times)

Yiqi Shi

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Quiz 1-P2
« on: October 01, 2015, 11:44:08 PM »
Find the general solutions to
\begin{equation}
u_{xxyy}=\sin(x)\sin(y);
\label{eq1}
\end{equation}

Solution:
\begin{equation}
u_{xxy}=-\sin(x)\cos(y)+\phi(x);
\label{eq2}
\end{equation}

\begin{equation}
u_{xx}=-\sin(x)\sin(y)+y\phi(x)+\psi(x);
\label{eq3}
\end{equation}

\begin{equation}
u_{x}=\cos(x)\sin(y)+y\int \phi(x)\,dx+\int\psi(x)\,dx+h(y)=\cos(x)\sin(y)+yf(x)+g(x)+h(y);
\label{eq4}
\end{equation}

\begin{equation}
u=\sin(x)\sin(y)+y\int f(x)\,dx+\int g(x)\,dx+xh(y)+\eta(y)=\sin(x)\sin(y)+yF(x)+G(x)+xh(y)+\eta(y);
\label{eq5}
\end{equation}