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Re: Misner, Thorne and Wheeler, Exercise 8.5 (c)
Posted:
Apr 13, 2013 10:55 AM


On Apr 13, 1:54 am, "Dono." <sa...@comcast.net> wrote: > On Apr 8, 6:08 pm, rotchm <rot...@gmail.com> wrote:> > which again with [1] gives > > > r r''' + 3 r'' r' = 0 > > > > So if you find some r(t) that has r''(t) = r'''(t) = 0 for all t, > > > you're done. Easy. Take > > > r(t) = A t + B [3] > > > Yes, thats a "trivial" solution and as you hinted, there are others. > > The general solution to this is > > r = s(At2 + Bt + C), which can be ~ at + b if its a perfect square. > > No, pretentious imbecile, what you put down is not a solution since r" > isn't null for all t (while r"'=0).
1) ?? Didnt you see DvDM's reply to me? He agreed that what I put down is a solution to r r''' + 3 r'' r' = 0.
Try it. You can do it by direct substitution!! TRY IT !!
2) You seem to impose that r'' must equal zero. Why? It need not be.
3) Now, you seem to have also misinterpreted (your incapacity to deduce) the notation of s(...). DvDM did understand it. You didnt read those who replied to me? That is quite sloppy on your part.
4) Try again.


Date

Subject

Author

4/7/13


Guest

4/7/13


Lord Androcles, Zeroth Earl of Medway

4/8/13


Lord Androcles, Zeroth Earl of Medway

4/8/13


Hetware

4/8/13


Lord Androcles, Zeroth Earl of Medway

4/8/13


Hetware

4/9/13


Lord Androcles, Zeroth Earl of Medway

4/9/13


Hetware

4/8/13


Hetware

4/8/13


Lord Androcles, Zeroth Earl of Medway

4/9/13


Hetware

4/9/13


Lord Androcles, Zeroth Earl of Medway

4/9/13


Hetware

4/9/13


Lord Androcles, Zeroth Earl of Medway

4/9/13


Hetware

4/8/13


Dirk Van de moortel

4/8/13


Lord Androcles, Zeroth Earl of Medway

4/8/13


rotchm@gmail.com

4/9/13


Dirk Van de moortel

4/13/13


Dono

4/13/13


rotchm@gmail.com

4/13/13


Dono

4/13/13


Dono

4/13/13


Dono

4/13/13


rotchm@gmail.com

4/13/13


Dono

4/13/13


rotchm@gmail.com

4/13/13


Dono

4/13/13


Dono

4/13/13


rotchm@gmail.com

4/13/13


Dono

4/13/13


rotchm@gmail.com

4/13/13


Dono

4/9/13


Guest

4/9/13


Dirk Van de moortel

4/9/13


Lord Androcles, Zeroth Earl of Medway

4/8/13


Rock Brentwood

4/8/13


Hetware

4/8/13


Lord Androcles, Zeroth Earl of Medway


