The 2D Wave Equation on a Square;

Homogeneous Dirichlet Boundary Conditions

 $cos\left(21/2t\right) sin\left(x\right) sin\left(y\right)$ $cos\left(51/2t\right) sin\left(2x\right) sin\left(y\right)$ $cos\left(101/2t\right) sin\left(3x\right) sin\left(y\right)$ $cos\left(51/2t\right) sin\left(x\right) sin\left(2y\right)$ $cos\left(81/2t\right) sin\left(2x\right) sin\left(2y\right)$ $cos\left(131/2t\right) sin\left(3x\right) sin\left(2y\right)$ $cos\left(101/2t\right) sin\left(x\right) sin\left(3y\right)$ $cos\left(131/2t\right) sin\left(2x\right) sin\left(3y\right)$ $cos\left(181/2t\right) sin\left(3x\right) sin\left(3y\right)$

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