Question: another odetest challenge

This solution by dsolve is correct. I get same solution. The problem is odetest does not give zero.

All my simplification attempts failed and adding assumptions to call to odetest does not change anything for what I tried. i.e. could not make Maple show that the result of odetest is zero.

Any one can come up with smart way to verify this solution is correct? 

interface(version);

`Standard Worksheet Interface, Maple 2025.0, Linux, March 24 2025 Build ID 1909157`

restart;

ode:=diff(y(x),x)*(x-ln(diff(y(x),x))) = 1;
maple_sol:=dsolve(ode);

(diff(y(x), x))*(x-ln(diff(y(x), x))) = 1

y(x) = -(1+LambertW(-exp(-x))*x+LambertW(-exp(-x))^2)/LambertW(-exp(-x))+c__1

the_residue:=odetest(maple_sol,ode);

(-x+ln(-1/LambertW(-1/exp(x)))-LambertW(-1/exp(x)))/LambertW(-1/exp(x))

Digits:=100;
plot(the_residue,x=0..10)

100

 

 

Download odetest_challange_may_15_2025.mw

Note that coulditbe(the_residue=0) gives true, but this is not reliable way to check, so this method does not coumt.

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