generating solvable DEs



Somewhat off-topic, but if you are writing a DE final examination this
weekend,  you may
enjoy  the short Maxima program:

gen_de(sol, dvar, ivar, const) := block([de ],
     sol : [sol, diff(sol,ivar),diff(sol,ivar,2)],
     de : eliminate(sol, const),
     de : solve(de, diff(dvar,ivar,2)),
    ratsimp(first(de))
)$

(c1) depends(y,x)$

(c2) gen_de(y=k1*(x+x^3)*x^(-3/2) + k2 * x*x^(-3/2),y,x,[k1, k2]);

(c3) 'diff(y,x,2) = 3*y/(4*x^2)

(c4) latex(%);

$$ \frac {d^{2} y}{d x^{2}}=\frac {3\,y}{4\,x^{2}} $$

Wunderbar.   To me Maxima is fun, but it also about doing real work quickly and accurately.
For all the folks that have made this possible, I thank you.

--blw