GraphingCalculator 4;
Window 51 34 863 1413;
PaneDivider 413;
SignificantDigits 14;
FontSizes 18;
StackPanes 1;
2D.Scale 0.05 0.05 2 2;
2D.BottomLeft -1.15 -1.54375;
Expr function(f,x,y)=[2*x^2+5*y^2]*[1+1/4*cos([7*atan([y/x])])];
Color 8;
Expr function(p,x,y)=function(oppartial(x),function(f,x,y)),function(q,x,y)=function(oppartial(y),function(f,x,y));
Color 2;
Expr 1=function(f,x,y);
Color 3;
Expr 2=function(f,x,y);
Color 4;
Expr 3=function(f,x,y);
Expr 4=function(f,x,y);
Expr function(f,x,y)=k,in(k,set(5,6,7));
Text "<size=11>Why doesn't that work?  Grrr.";
Color 3;
Expr 5=function(f,x,y);
Color 4;
MathPaneSlider 11;
Expr T=slider([0,2*pi]);
Color 6;
Expr c=3/4*cos(T),d=3/4*sin(T);
Color 17;
Expr vector(c,d),vector(c,d)+1/50*vector(function(p,c,d),function(q,c,d));
Color 8;
Expr R=sqrt(3/function(f,cos(T),sin(T))),a=R*cos(T),b=R*sin(T);
Text "<size=11>The ""3"" in this formula is the contour on which the gradient is rooted in this example";
Expr vector(a,b),vector(a,b)+1/50*vector(function(p,a,b),function(q,a,b));
Text "<size=11>
Author: David A. Craig <<http://web.lemoyne.edu/~craigda/>";