Input:
pdsolve(ds(y,t)-ds(y,x,2)=2z-2y,ds(z,t)-ds(z,x,2)=4z-4y)
Write:
`pdsolve(ds(y,t)-ds(y,x,2)=2z-2y,ds(z,t)-ds(z,x,2)=4z-4y)`
Compute:
$$pdsolve(\frac{dy}{dt} - \frac{d^{{2}}y}{dx^{{2}}}=2\ z - 2\ y,\frac{dz}{dt} - \frac{d^{{2}}z}{dx^{{2}}}=4\ z - 4\ y)$$
Output:
$$pdsolve(\frac{dy}{dt} - \frac{d^{{2}}y}{dx^{{2}}}=2\ z - 2\ y,\frac{dz}{dt} - \frac{d^{{2}}z}{dx^{{2}}}=4\ z - 4\ y)== y=\frac{1}{8}\ (2\ (C_1\ cos(1.4142135623730951\ x)+exp(2\ (C_1+t))+C_2\ sin(1.4142135623730951\ x))-4\ (2\ C_1+C_2\ x))\ and\ z=\frac{1}{2}\ ((-2)\ C_1+C_1\ cos(1.4142135623730951\ x)+exp(2\ (C_1+t))+C_2\ sin(1.4142135623730951\ x)-C_2\ x)$$
Result: $$y=\frac{1}{8}\ (2\ (C_1\ cos(1.4142135623730951\ x)+exp(2\ (C_1+t))+C_2\ sin(1.4142135623730951\ x))-4\ (2\ C_1+C_2\ x))\ and\ z=\frac{1}{2}\ ((-2)\ C_1+C_1\ cos(1.4142135623730951\ x)+exp(2\ (C_1+t))+C_2\ sin(1.4142135623730951\ x)-C_2\ x)$$
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