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Question: why can't Maple solve this basic first order ode?

Question:why can't Maple solve this basic first order ode?

nm 11383 Maple 2025
ode dsolve implicit differential-equations
8 hours ago
1

Any idea why Maple dsolve can't find solution to this ode? From textbook

The strange thing, it solves if it asked for implicit solution. But the default, will give no solution.

Is this a defect? Should it not have returned the book solution automatically?   How is a user supposed to know the ode has a solution or not, if default call returns no solution?

> 

restart;
> 

interface(version);

`Standard Worksheet Interface, Maple 2025.1, Linux, June 12 2025 Build ID 1932578`

> 

SupportTools:-Version();

`The Customer Support Updates version in the MapleCloud is 29 and is the same as the version installed in this computer, created June 23, 2025, 10:25 hours Eastern Time.`

> 

Physics:-Version();

`The "Physics Updates" version in the MapleCloud is 1877 and is the same as the version installed in this computer, created 2025, July 11, 19:24 hours Pacific Time.`

> 

restart;
> 

ode:=v(x)*diff(v(x),x) = g;
ic:=v(x__0) = v__0;
sol:=dsolve([ode,ic]);

v(x)*(diff(v(x), x)) = g

v(x__0) = v__0

> 

restart;
> 

ode:=v(x)*diff(v(x),x) = g;
ic:=v(x__0) = v__0;
sol:=dsolve([ode,ic],'implicit');

v(x)*(diff(v(x), x)) = g

v(x__0) = v__0

-2*g*x+v(x)^2+2*g*x__0-v__0^2 = 0

> 

#why did not default call return this?
PDEtools:-Solve(sol,v(x))

v(x) = (2*g*x-2*g*x__0+v__0^2)^(1/2), v(x) = -(2*g*x-2*g*x__0+v__0^2)^(1/2)

Download dsolve_gives_no_solution_sept_2_2025.mw
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