input constantes; input geometriepoint1; u:=0.5cm; beginfig(1); affixec.O(u*(0,0))so; affixe.B(u*(0,-4)); affixe.S(u*(0,4)); path cc,cd; cc=cercle(O,3u); cd=cc yscaled 0.15; affixe.A(point((length cd)/2) of cd); draw z.S--z.A--(point((length cd)/2) of (cd shifted(z.B-z.O)))--(subpath((length cd)/2,length cd) of (cd shifted(z.B-z.O)))--(point(length cd) of cd)--cycle; draw subpath((length cd)/2,length cd) of cd; draw subpath(0,(length cd)/2) of cd dashed evenly; draw subpath(0,(length cd)/2) of (cd shifted(z.B-z.O)) dashed evenly; cotation(A,O,0,2mm,btex $R$ etex); cotationmil(B,O,-3.5u,10,btex $h$ etex); cotationmil(O,S,-3.5u,10,btex $h$ etex); endfig; u:=0.75cm; beginfig(2); affixe.D(u*(1,1))so; affixe.C(u*(8,1))se; affixe.B(u*(8,8))ne; affixe.A(u*(1,8))no; affixe.O(1/2[z.A,z.C])s; affixe.U(1/4[z.D,z.C])s; affixe.T(3/4[z.D,z.C])s; affixe.S(1/4[z.C,z.B])e; affixe.R(3/4[z.C,z.B])e; affixe.Q(1/4[z.B,z.A])n; affixe.P(3/4[z.B,z.A])n; affixe.N(1/4[z.A,z.D])o; affixe.M(3/4[z.A,z.D])o; affixe.H(1/2[z.A,z.D])o; cotation(M,N,1cm,2mm,btex $x$ etex); path aile; aile=z.O--z.P--z.A--z.N--z.O--z.M--z.D--z.U--z.O--z.T--z.C--z.S--z.O--z.R--z.B--z.Q--cycle; color gris; gris=0.4[white,black]; fill aile withcolor gris; draw aile; drawoptions(dashed evenly); draw z.O--z.H; draw z.N--z.M; draw z.U--z.T; draw z.S--z.R; draw z.Q--z.P; drawoptions(); draw codesegments(M,D,D,U,2); draw codesegments(T,C,C,S,2); draw codesegments(R,B,B,Q,2); draw codesegments(P,A,A,N,2); endfig; end