Input:
pdsolve(ds(y,t,2)-a^2*ds(y,x,2)-a^2*ds( y,u,2))
Write:
`pdsolve(ds(y,t,2)-a^2*ds(y,x,2)-a^2*ds( y,u,2))`
Compute:
$$pdsolve(\frac{d^{{2}}y}{dt^{{2}}} - {a}^{2}\ \frac{d^{{2}}y}{dx^{{2}}} - {a}^{2}\ \frac{d^{{2}}y}{du^{{2}}})$$
Output:
$$pdsolve(\frac{d^{{2}}y}{dt^{{2}}} - {a}^{2}\ \frac{d^{{2}}y}{dx^{{2}}} - {a}^{2}\ \frac{d^{{2}}y}{du^{{2}}})== 2\ C_1+C_2\ u+C_2\ x+2\ C_1\ ((-0.5)\ {u}^{2}+0.5\ {x}^{2})+0.5\ {x}^{2}\ y^{(2)}(t)$$
Result: $$2\ C_1+C_2\ u+C_2\ x+2\ C_1\ ((-0.5)\ {u}^{2}+0.5\ {x}^{2})+0.5\ {x}^{2}\ y^{(2)}(t)$$
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