Hello,

I have an ODE with three boundary conditions to solve (see code bellow). Having run this code as a .mlx file I see that cond2 is read as:

it takes the derivative in respects to a not r. I wanted to produce such a limit:

I tried changing the condition to:

`cond2 = Dw(r==a) == 0`

or

`cond2 = Dw(r=a) == 0`

but it did not do the trick. Could you please tell me how to properly input the boudary condition in respect to r?

Thank you,

Bellow is my code:

`clear; clc;syms a P G t nu F Q r D w(r) h% Forces`

F = - pi * a^2 * P;Q = (pi*r^2*P) / (2*pi*r);% ODE

ode = diff(((1/r)*diff((r*diff(w,r)),r)),r) == Q/D;Dw = diff(w,r);cond1 = Dw(0) == 0;cond2 = Dw(a) == 0cond3 = w(a) == 0;conds = [cond1 cond2 cond3];wSol(r) = dsolve(ode,conds);w_0 = subs(wSol,r,0);

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