Question: a problem in fsolve

hello.i have a problem for solving this equation.i dont why my past post about this is deleted.!!!

please help me

thanks,,,

9.mw
 

restart:

A1:= 27159:  n:= 0.59:  A2:= 70941:  h0:= 3e-4:   
L:= 0.8:  dpx := -98100:  uc:= 0.007:  k:=2.7:

ODE:= (A3,y)->
   (h0^(n+1)*L/sqrt(n)*(A1*exp(sqrt(n)*y/L)-A2*exp(-sqrt(n)*y/L))/k+dpx*y*h0^(n+1)/k+A3*(h0)^n/k)^(1/n)
;

proc (A3, y) options operator, arrow; (h0^(n+1)*L*(A1*exp(sqrt(n)*y/L)-A2*exp(-sqrt(n)*y/L))/(sqrt(n)*k)+dpx*y*h0^(n+1)/k+A3*h0^n/k)^(1/n) end proc

(1)

ODEINT:= proc(A3)
option remember;
local y;
   evalf(Int(ODE(A3,y), y= 0..1, epsilon= 1e-7)) - uc
end proc:

ReINT:= proc(A3x, A3y)
   Digits:= 15:
   Re(ODEINT(A3x + I*A3y))
end proc:

ImINT:= subs(Re= Im, eval(ReINT)):

Digits:= 7:
a3:= fsolve([ReINT, ImINT]);

fsolve([ReINT, ImINT])

(2)

A3:= Complex(a3[]);

Complex(fsolve([ReINT, ImINT])[])

(3)

Solve as IVP:

Digits:= 15:
sol:= dsolve({diff(u(y),y) = ODE(A3,y), u(0)=0}, numeric, range=0..1,  output=listprocedure):

Warning,  computation interrupted

 

NULL

``

NULL

NULL

plots:-odeplot(
   sol, [[y, Re(u(y))], [y, Im(u(y))]], y= 0..1,
   legend= [real, imag], labels= [y, u(y)]
);

Verify that boundary condition at u(1) is satisfied:

 

 

 

abs(eval(u(y), sol(1)) - uc);

sol(.5);

"\"

fy3 := eval(u(y), sol); with(CurveFitting); fy33 := PolynomialInterpolation([[0, fy3(0)], [.1, fy3(.1)], [.2, fy3(.2)], [.3, fy3(.3)], [.4, fy3(.4)], [.5, fy3(.5)], [.6, fy3(.6)], [.7, fy3(.7)], [.8, fy3(.8)], [.9, fy3(.9)], [1, fy3(1)]], y)

DEBI := int(fy33, y = 0 .. 1)

NULL

``

plot(DEBI, y = 0 .. 1)

``

``

``

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``


 

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