Elipsa

>	xt1:=5*cos(t);

>	yt1:=3*sin(t);

>	plot([xt1,yt1,t=0..2*Pi],scaling=constrained);

>	animate([5*cos(t*k),3*sin(t*k),t=0..2*Pi],k=0..1,frames=100,scaling=constrained);

>	with(plots):

>