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### desolve initial condition involving e gives strange answer

I'm trying to do some basic differential equations in Sage. When I run the following:

var('t')

y = function('y')(t)

de1 = t^3diff(y, t) + 4t^2*y == e^(t^2)

desolve(de1, y, ics = [1,e])

The output is

1/2*(e^(t^2) + y(t))/t^4

My expectation is that there shouldn't by any y(t) term in the output. If I make a seemingly meaningless tweak to my initial conditions:

desolve(de1, y, ics = [1,e*1])

I get the expected output of

1/2*(e + e^(t^2))/t^4

If I change the initial conditions to [1, e/2], I again get the output I expect. I haven't been able to reproduce this issue with any other example. Maybe the issue just comes in converting Sage's version of e into Maxima? Does anyone know what is going on here?

### desolve initial condition involving e gives strange answer

I'm trying to do some basic differential equations in Sage. When I run the following:

var('t')   var('t')  y = function('y')(t) function('y')(t)
de1 = t^3diff(y, t^3*diff(y, t) + 4t^2*y 4*t^2*y == e^(t^2) e^(t^2)
desolve(de1, y, ics = [1,e]) 
[1,e]) 

The output is

1/2*(e^(t^2) + y(t))/t^4 
y(t))/t^4 

My expectation is that there shouldn't by any y(t) term in the output. If I make a seemingly meaningless tweak to my initial conditions:

desolve(de1, y, ics = [1,e*1]) 
[1,e*1]) 

I get the expected output of

1/2*(e + e^(t^2))/t^4 
e^(t^2))/t^4 

If I change the initial conditions to [1, e/2], I again get the output I expect. I haven't been able to reproduce this issue with any other example. Maybe the issue just comes in converting Sage's version of e into Maxima? Does anyone know what is going on here?

 3 retagged tmonteil 23793 ●25 ●171 ●438 http://wiki.sagemath.o...

### desolve initial condition involving e gives strange answer

I'm trying to do some basic differential equations in Sage. When I run the following:

var('t')
y = function('y')(t)
de1 = t^3*diff(y, t) + 4*t^2*y == e^(t^2)
desolve(de1, y, ics = [1,e])


The output is

1/2*(e^(t^2) + y(t))/t^4


My expectation is that there shouldn't by any y(t) term in the output. If I make a seemingly meaningless tweak to my initial conditions:

desolve(de1, y, ics = [1,e*1])


I get the expected output of

1/2*(e + e^(t^2))/t^4


If I change the initial conditions to [1, e/2], I again get the output I expect. I haven't been able to reproduce this issue with any other example. Maybe the issue just comes in converting Sage's version of e into Maxima? Does anyone know what is going on here?