4-12 Construct the figure

> restart:

> x:=cos(t):

> y:=sin(t):

> r:=((x-3*cos(t)/4-cos(3*t)/4)^2+(y-3*sin(t)/4+sin(3*t)/4)^2)^(1/2):

> m:=[x+r*cos(s),y+r*sin(s),s=0..2*Pi]:

> t:=2*Pi*n/100:

> plot([m$n=0..100],color=red,scaling=constrained,axes=none);

>