Budeme resit rce

dery[x_, y_] = 
        5;

    y0 = 1;

    xmax = 6;

    resanal = DSolve[{y'[x] == dery[x, y[x]], 
              y[0] == y0}, y[x], x][[1]];

    protiskanal = y[x] /. resanal;

    n = 10;

    h = (xmax/n);

    startovacibod = {0. , y0};

    EulerKrok[{x_, y_}] := {x + h, y + dery[x, y]*h};

    bodiky = NestList[EulerKrok, startovacibod, n]

    p2 = 
        ListPlot[bodiky, PlotStyle -> PointSize[ .03], 
          AxesLabel -> {"x", "y[x]"}, 
          DisplayFunction -> Identity];

    p1 = 
        Plot[protiskanal, {x, 0, xmax}, 
          PlotStyle -> {Hue[0.9], Thickness[0.02]}, 
          AxesLabel -> {"x", "y[x]"}, 
          DisplayFunction -> Identity];

    Show[p1, p2, DisplayFunction -> $DisplayFunction]