Circle centered at (2,1) of radius 3.

>    f:=2+3*cos(theta);

f := 2+3*cos(theta)

>    g:=1+3*sin(theta);

g := 1+3*sin(theta)

>    plot([f,g,theta=0..2*Pi]);

[Maple Plot]

Lissajous figures: (x,y)=(cos(pt),sin(qt)), where p and q are relatively prime.

>    p:=3; q:=2;

p := 3

q := 2

>    f:=cos(p*t); g:=sin(q*t);

f := cos(3*t)

g := sin(2*t)

>    plot([f,g,t=0..2*Pi]);

[Maple Plot]

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