Input:
pdsolve(ds(y,t,2)-a^2*ds(y,x,2))
Write:
`pdsolve(ds(y,t,2)-a^2*ds(y,x,2))`
Compute:
$$pdsolve(\frac{d^{{2}}y}{dt^{{2}}} - {a}^{2}\ \frac{d^{{2}}y}{dx^{{2}}})$$
Output:
$$pdsolve(\frac{d^{{2}}y}{dt^{{2}}} - {a}^{2}\ \frac{d^{{2}}y}{dx^{{2}}})== 2\ C_1+C_2\ t+C_2\ x+C_4\ t\ x+C_1\ ((\frac{-1}{2})\ {a}^{2}\ {t}^{2}-\frac{1}{2}\ {x}^{2})$$
Result: $$2\ C_1+C_2\ t+C_2\ x+C_4\ t\ x+C_1\ ((\frac{-1}{2})\ {a}^{2}\ {t}^{2}-\frac{1}{2}\ {x}^{2})$$
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