derivative of ODE

[XcasEngGuy]

Is there a way to differentiate or integrate ODEs?

For example:

d/dt(1/2*m*(d2/d2t(x))^2+1/2*k*x^2)

where d2/d2t(x) is the second derivative of x w/respect to t and d/dt represents taking the derivative (which I would like to do in xcas)

I hope this is clear.

I should get:

m*d/dt(x)*d2/d2t(x)+k*x*d/dt(x)

[parisse]

You should be able to do that by replacing x by a function x(t)

[XcasEngGuy]

I don't quite understand. I tried using diff on eq1:=5*x(t) and got 5*diff(x(t),t) and using diff again got 5*diff(x(t),t,2). Is that what you meant?

Thanks
Matt

[parisse]

Yes.

[XcasEngGuy]

Thanks. Once I got used to it, it works very well.