Can this be solved with any HP CAS?

[Gilles59]

(09-28-2017 07:43 PM)Csaba Tizedes Wrote:  

(09-27-2017 08:56 PM)Gilles59 Wrote:  I suppose that the CAS simplify too much ;D

PS.: No any CAS which can solve this problem correctly... This is too simple to handle it correctly. Of course the triple integrals in negative dimensions on a hyperboloid surface can do without problem, but I'm an engineer and I want RELIABLE solutions.

Hi CSaba

The HP Prime returns the correct answer {}
The old hp50 cas simplify the équation in 3x=15. but we have a brain. A cas is just a tool. This limitation of DOMAIN for the 50g is explain in the doc.

You are engineer. Perhaps for your problem x=5+/- epsilon could be an interesting approximate solution. For an engineer the question is : what means x=5 in the system? Infinite length? Infinite force? Undeground altitude? Negative mass? Why x=5 is impossible in a physical point of view? For an engineer mathematic is just a tool in my point of view.