> restart;

> u := (x,y) -> 15* exp( -sqrt(5)*9*Pi*Pi/4*y)*cos(3*Pi/2 *x) + 16 *exp(-sqrt(5)*29241*Pi*Pi/4 *y) *cos(171*Pi/2 *x);

> plot3d( u(x,y), x=0..2, y=0..0.04, labels =[`x`, `time`, `u(x,t)`], axes=FRAMED, style=patch);

>