Line Integral of Vector Field

> with(plots):

> f1:=cos(t);

> f2:=sin(t);

> F1:=1/(y+0.1);

> F2:=-1/(x+0.1);

> plot1:=fieldplot([F1,F2],x=0.01..1,y=0.01..1,color=blue):

> plot2:=plot([f1,f2,t=0..Pi/2]):

> display({plot1,plot2});

> work:=int((1/(1+f2))*diff(f1,t)-(1/(1+f1))*diff(f2,t),t=0..Pi/2);

>