# Differential equations – NDSolve error: Solution not possible to find an explicit formula for the derivatives. Consider using the Method -> {"EquationSimplification" -> "Residual" option} I get the above error message when running the following code:

``````[Alpha]h = 0.2; [Alpha]z = 0.2; [Gamma] = 0.5; ph = 0.01; pf =
0.1; pE = 0.05; FC = 0.1; FE = 0.15; tC = 0.01; tE = 0; TC = 0.05; TE
= -0.05; w = 1; [Rho] = 0.2; [Sigma] =
1 / (1 - [Rho]); L = 1; RA = 0.25; [Mu] = 1;
G = 1; R0 = 0.1; S = 1;

v[s_] : = [Mu] log[
Exp[([([([([Alpha]h ((RC[s] +
ph) ^ (- ([Rho]/ [Sigma])) + ([Alpha]H / [Alpha]z) ^ (- (
[Rho]/ [Sigma]))) ^ ((
1 - [Rho])[Rho]) (w + G + R0 / L - (pf + tC) s - FC -
TC) - [Gamma]  Integrate[
LogisticSigmoid[
x] (([Alpha]H / [Alpha]z) ^ (- ([Rho]/ [Sigma])) + (RC[x] +
ph) ^ (- ([Rho]/ [Sigma])) / ((RC[x] +
ph) ^ - [Sigma]   (w + G + R0 / L - (pf + tC) x - FC -
TC)), {x, s, S}])[Mu]]+
Exp[([([([([Alpha]h ((RC[s] +
ph) ^ (- ([Rho]/ [Sigma])) + ([Alpha]H / [Alpha]z) ^ (- (
[Rho]/ [Sigma]))) ^ ((
1 - [Rho])[Rho]) (w + G + R0 / L - (pE + tE) s - FE -
TE) - [Gamma]  Integrate[(1 -
LogisticSigmoid[
x]) (([Alpha]H / [Alpha]z) ^ (- ([Rho]/ [Sigma])) + (RC[
x] + ph) ^ (- ([Rho]/ [Sigma])) / ((RC[x] +
ph) ^ - [Sigma]   (w + G + R0 / L - (pf + tC) x - FC -
TC)), {x, s, S}])[Mu]]];

sol = FullSimplify[Tosolve[{D[v[Solve[{D[v[Lösen[{D[v[Solve[{D[v[s]s]== 0}, RC & # 39;[s]]]solprime = Equal Flatten[sol];
solND = NDSolve[{solprime[], RC[S] == RA}, RC, {s, 0, S}]
``````

I tried to add the suggested method as well as the method -> {"EquationSimplification" -> "Solve"}, but got some other error messages after some time of calculation.
Either "NDSolve :: idelay: The initial history must be specified for all variables for delay differential equations." or "StringForm :: sfr: Element 2" requested in "Delayed time `1` = `2` calculated by `3` = `4` not evaluated to a real number. "out of range; 1 article available."

Any advice would be very grateful. Many Thanks! Posted on Categories Articles