Input:
pdsolve(ds(y,t,2)-a^2*ds(y,x,2)-a^2*ds( y,u,2)-a^2*ds(y,v,2))
Write:
`pdsolve(ds(y,t,2)-a^2*ds(y,x,2)-a^2*ds( y,u,2)-a^2*ds(y,v,2))`
Compute:
$$pdsolve(\frac{d^{{2}}y}{dt^{{2}}}-{a}^{2}\ \frac{d^{{2}}y}{dv^{{2}}}-{a}^{2}\ \frac{d^{{2}}y}{du^{{2}}}-{a}^{2}\ \frac{d^{{2}}y}{dx^{{2}}})$$
Output:
$$pdsolve(\frac{d^{{2}}y}{dt^{{2}}}-{a}^{2}\ \frac{d^{{2}}y}{dv^{{2}}}-{a}^{2}\ \frac{d^{{2}}y}{du^{{2}}}-{a}^{2}\ \frac{d^{{2}}y}{dx^{{2}}})== C_1+C_2\ exp(1.7320508075688774i\ a\ t)\ sin(u)\ sin(v)\ sin(x)$$
Result: $$C_1+C_2\ exp(1.7320508075688774i\ a\ t)\ sin(u)\ sin(v)\ sin(x)$$
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