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:
$$pdsolve(\frac{d^{{2}}y}{dt^{{2}}}-{a}^{2}\ \frac{d^{{2}}y}{du^{{2}}}-{a}^{2}\ \frac{d^{{2}}y}{dx^{{2}}})$$
Output:
$$pdsolve(\frac{d^{{2}}y}{dt^{{2}}}-{a}^{2}\ \frac{d^{{2}}y}{du^{{2}}}-{a}^{2}\ \frac{d^{{2}}y}{dx^{{2}}})== 2\ c_1+"undefined"\ C_1\ log(a)+c_2\ u+c_2\ x+C_1\ ((-0.5)\ {a}^{2}\ {u}^{2}+0.5\ {a}^{2}\ {x}^{2})+0.5\ \frac{1}{a^2}\ {x}^{2}\ y^{(2)}(t)$$
Result: $$2\ c_1+"undefined"\ C_1\ log(a)+c_2\ u+c_2\ x+C_1\ ((-0.5)\ {a}^{2}\ {u}^{2}+0.5\ {a}^{2}\ {x}^{2})+0.5\ \frac{1}{a^2}\ {x}^{2}\ y^{(2)}(t)$$
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