cancel
Showing results for 
Search instead for 
Did you mean: 
cancel
Showing results for 
Search instead for 
Did you mean: 

Community Tip - You can subscribe to a forum, label or individual post and receive email notifications when someone posts a new topic or reply. Learn more! X

Boundary problem with f(x):=Odesolve...

ValeryOchkov
24-Ruby IV

Boundary problem with f(x):=Odesolve...

I would like to solve one ODEs boundary problem (find v) with using user functions based on the Odesolve function.

But

1. Cannot use root or Find functions

2. Very slowly calculation

3. I must restart my Prime 6

etc

Help please!

PS

I cannot write this problem in Polar coordinates! See attach.

5 REPLIES 5

One error:

Fred_Kohlhepp_0-1636030041033.png

By inspection r(0 s) = a

LucMeekes
23-Emerald III
(To:Fred_Kohlhepp)

No,

at t=0, the comet is at (-a,0), its distance to the sun (r) then is a+c.

 

Luc

You're right, as usual!

I need to read more carefully.

LucMeekes
23-Emerald III
(To:ValeryOchkov)

How about (Mathcad 11, cannot use units):

LucMeekes_0-1636062694602.png

LucMeekes_2-1636062773936.png

LucMeekes_3-1636062843451.png

Calculate the speed from the x and y speeds:

LucMeekes_5-1636062927300.png

Success!
Luc

 

 

 

Thanks, Luc!

No problem with X-Y-coordinats

Problems with Polar - see please pdf in attach (and Prime 6)

Announcements

Top Tags