Help with PDE: F(t)g(r)+V/R Derivative

  • Thread starter Thread starter matteo86bo
  • Start date Start date
  • Tags Tags
    Pde
matteo86bo
Messages
56
Reaction score
0
I need help with this PDE, it's not an homework, I need to solve it for my thesis and it has physical application...anyway the problem is:
<br /> \frac{dx}{dt}=f(t)g(r)+\frac{v}{r}\frac{d (Rx)}{dR}<br /> <br />

f(t) and g(r) are known.

I can solve the equation with only the first or the second term ...
actually I'm interest in how the second term modify the solution of the equation with the first term only. suggestions?
 
Physics news on Phys.org
Your PDE can be solved with help of Laplace transform method. For your purpose it'll be better the following form of general solution ( I assume that in fact R is r)

x(t,r) = \frac{1}{r}[\int_c^tf(\xi)g(vt-v\xi+r)(vt-v\xi+r)d\xi+F(vt+r)],

where F(z) is an arbitrary function, c is an arbitrary constant.
 
Last edited:
Thread 'Direction Fields and Isoclines'
I sketched the isoclines for $$ m=-1,0,1,2 $$. Since both $$ \frac{dy}{dx} $$ and $$ D_{y} \frac{dy}{dx} $$ are continuous on the square region R defined by $$ -4\leq x \leq 4, -4 \leq y \leq 4 $$ the existence and uniqueness theorem guarantees that if we pick a point in the interior that lies on an isocline there will be a unique differentiable function (solution) passing through that point. I understand that a solution exists but I unsure how to actually sketch it. For example, consider a...
Back
Top