Student Support Forum: 'NDSolve errors' topicStudent Support Forum > General > "NDSolve errors"

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 Author Comment/Response Max 09/05/06 2:06pm Hello everyone, I'm trying to numerically solve a differential equation of the form: u[z] u'[z]==C1+(-C2*(C3-z)/z)(C4+C5 u[z] with a boundary condition u[-C6]==0 I first get the error Power::infy : Infinite expression 1/0. encountered and then the error NDSolve::ndum : encountered non-numerical value for a derivative at z=-C6... Any help understanding the second message would be much appreciated. Thanks, Max Here is the actual NDSolve input: \!\(\* RowBox[{"NDSolve", "[", RowBox[{ RowBox[{"{", RowBox[{ RowBox[{ RowBox[{\(u[z]\), " ", RowBox[{ SuperscriptBox["u", "?", MultilineFunction->None], "[", "z", "]"}]}], "==", \(\(\(9.8`\)\(\[InvisibleSpace]\)\) - \ \(0.00025700061842918987`\ \((273 - z\/50)\)\ \((\(\(29400.000000000004`\)\(\[InvisibleSpace]\)\) \ + 900\ u[z])\)\)\/z\)}], ",", \(u[10000] == 0\)}], "}"}], ",", "u", ",", \({z, 10, 100}\)}], "]"}]\) URL: ,
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