Question: Error in dsolve/numeric

Hai everyone

may i ask why solution have an error?

hope i have an answer

r

 

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restart

with(plots):

Pr := 6.8:

Eq1 := (101-100*lambda)*(diff(f(eta), `$`(eta, 3)))+f(eta)*(diff(f(eta), `$`(eta, 2)))+2*delta*theta(eta)+2*delta*Nc*gamma(eta)-2*delta*Nr*phi(eta);

(101-100*lambda)*(diff(diff(diff(f(eta), eta), eta), eta))+f(eta)*(diff(diff(f(eta), eta), eta))+2*theta(eta)+2*gamma(eta)-2*phi(eta)

(1)

Eq2 := (101-100*lambda)*(diff(theta(eta), `$`(eta, 2)))+Pr*f(eta)*(diff(theta(eta), eta))+Pr*Nb*(diff(theta(eta), eta))*(diff(phi(eta), eta))+Pr*Nt*(diff(theta(eta), eta))^2;

(101-100*lambda)*(diff(diff(theta(eta), eta), eta))+6.8*f(eta)*(diff(theta(eta), eta))+3.40*(diff(theta(eta), eta))*(diff(phi(eta), eta))+3.40*(diff(theta(eta), eta))^2

(2)

Eq3 := (101-100*lambda)*(diff(phi(eta), `$`(eta, 2)))+Le*f(eta)*(diff(phi(eta), eta))+Nt*(diff(theta(eta), `$`(eta, 2)))/Nb;

(101-100*lambda)*(diff(diff(phi(eta), eta), eta))+.1*f(eta)*(diff(phi(eta), eta))+1.000000000*(diff(diff(theta(eta), eta), eta))

(3)

Eq4 := (101-100*lambda)*(diff(gamma(eta), `$`(eta, 2)))+Sc*s*(diff(theta(eta), `$`(eta, 2)))+Sc*f(eta)*(diff(gamma(eta), eta));

(101-100*lambda)*(diff(diff(gamma(eta), eta), eta))+.30*(diff(diff(theta(eta), eta), eta))+.6*f(eta)*(diff(gamma(eta), eta))

(4)

VBi := [10, 20, 30]:

etainf := 5:

bcs := f(0) = 0, (D(f))(0) = 0, (D(theta))(0) = -Bi*(1-theta(0)), phi(0) = 1, gamma(0) = 1, (D(f))(etainf) = 1, theta(etainf) = 0, phi(etainf) = 0, gamma(etainf) = 0;

f(0) = 0, (D(f))(0) = 0, (D(theta))(0) = -Bi*(1-theta(0)), phi(0) = 1, gamma(0) = 1, (D(f))(5) = 1, theta(5) = 0, phi(5) = 0, gamma(5) = 0

(5)

dsys := {Eq1, Eq2, Eq3, Eq4, bcs}:

for i to 3 do Bi := VBi[i]; dsol[i] := dsolve(dsys, numeric, continuation = lambda); print(Bi); print(dsol[i](0)) end do

Error, (in dsolve/numeric/bvp) cannot determine a suitable initial profile, please specify an approximate initial solution

 

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