Re: Schaums outline Mathematica 2nd ed, prob. 11.3 help

*To*: mathgroup at smc.vnet.net*Subject*: [mg125738] Re: Schaums outline Mathematica 2nd ed, prob. 11.3 help*From*: David Reiss <dbreiss at gmail.com>*Date*: Fri, 30 Mar 2012 04:38:27 -0500 (EST)*Delivered-to*: l-mathgroup@mail-archive0.wolfram.com*References*: <jl14v2$lbd$1@smc.vnet.net>

One of the x's in your Dsolve is a capital X rather than a lower case x. Use DSolve[{y'[x] == x^2 + y[x], y[0] == k}, y[x], x], {k, 0, 4}]; rather than DSolve[{y'[x] == X^2 + y[x], y[0] == k}, y[x], x], {k, 0, 4}]; --David On Mar 29, 4:02 am, "pennsylvaniaj... at gmail.com" <pennsylvaniaj... at gmail.com> wrote: > I cannot get this code to show the solutions to the equation, only the vector plot. Whats wrong? It came from Schum's Outline, Mathematica 2n ed, solved problem 11.3 on page 272-3. The only changes I made was using v1 for vf and s1 for solutions. > > v1 = VectorPlot[{1, x^2 + y}, {x, 0, 1}, {y, 0, 12}, > Axes -> Automatic, VectorScale -> Tiny]; > > s1 = Table[ > DSolve[{y'[x] == X^2 + y[x], y[0] == k}, y[x], x], {k, 0, 4}]; > > Do[g[k] = > Plot[s1[[k, 1, 1, 2]], {x, 0, 1}, PlotStyle -> Thickness[0.007], > PlotRange -> All], {k, 1, 5}] > > Show[g[1], g[2], g[3], g[4], g[5], v1, Frame -> True, > AspectRatio -> 1]