D:\j_Iam_TEMP\_jh\jh_k123_momentForce_v3.wxmx
~/.maxima/deriv.mac и выполнять в Maxima строку load(deriv)$ deriv(какое-нибудь-выражение);
https://maxima.sourceforge.io/ru/maxima-tarnavsky-6-diff.html
(%i36) kill(all);

\[\]\[\tag{%o0} \ensuremath{\mathrm{done}}\]

L1-x1,L2-x2,L-x... - coordinates,start with L-x
(%i6) G1:1;G2:2;x1:−5;x2:1;G:G1+G2;x:12;

\[\]\[\tag{%o1} 1\]

\[\]\[\tag{%o2} 2\]

\[\]\[\tag{%o3} \mathop{-}5\]

\[\]\[\tag{%o4} 1\]

\[\]\[\tag{%o5} 3\]

\[\]\[\tag{%o6} 12\]

(%i9) sW:[G1,G2,G,x1,x2,x];sS:['G1,'G2,'G,'x1,'x2,'x,'L];sU:['N,'N,'N,'m,'m,'m,"?"];

\[\]\[\tag{%o7} \left[ 1\mathop{,}2\mathop{,}3\mathop{,}\mathop{-}5\mathop{,}1\mathop{,}12\right] \]

\[\]\[\tag{%o8} \left[ \ensuremath{\mathrm{G1}}\mathop{,}\ensuremath{\mathrm{G2}}\mathop{,}G\mathop{,}\ensuremath{\mathrm{x1}}\mathop{,}\ensuremath{\mathrm{x2}}\mathop{,}x\mathop{,}L\right] \]

\[\]\[\tag{%o9} \left[ N\mathop{,}N\mathop{,}N\mathop{,}m\mathop{,}m\mathop{,}m\mathop{,}"?"\right] \]

(%i10) fstr3(sW,sS,sU):=block([l,eqq,w,u,my_string],
    l:sconcat(sS),
    eqq:sconcat("="),
    w:string(sW),
    u:concat(sU),
   my_string:concat(l,eqq,w,u),
return (my_string));

\[\]\[\tag{%o10} \mathop{fstr3}\left( \ensuremath{\mathrm{sW}}\mathop{,}\ensuremath{\mathrm{sS}}\mathop{,}\ensuremath{\mathrm{sU}}\right) \mathop{:=}\]

(%i11) text_string:fstr3(sW[1],sS[1],sU[1]);

\[\]\[\tag{%o11} "G1=1N"\]

(%i12) fstr_sum(sW,sS,sU,G1,G2):=block([name,eqq,plus,w,u,g1,g2,my_string],
    name:sconcat(sS),
    eqq:sconcat("="),
    plus:sconcat("+"),
    w:string(sW),
    u:concat(sU),
    g1:G1,
    g2:G2,
   my_string:concat(name,eqq,g1,u,plus,g2,u,eqq,w,u),
return (my_string));

\[\]\[\tag{%o12} \mathop{fstr\_ sum}\left( \ensuremath{\mathrm{sW}}\mathop{,}\ensuremath{\mathrm{sS}}\mathop{,}\ensuremath{\mathrm{sU}}\mathop{,}\ensuremath{\mathrm{G1}}\mathop{,}\ensuremath{\mathrm{G2}}\right) \mathop{:=}\]

(%i13) fstr_sum(sW[3],sS[3],sU[3],G1,G2);

\[\]\[\tag{%o13} "G=1N+2N=3N"\]

(%i15) size1:sqrt(G1),numer;size2:sqrt(G2),numer;

\[\]\[\tag{%o14} 1.0\]

\[\]\[\tag{%o15} 1.4142135623730951\]

(%i16) del1:0.5;

\[\]\[\tag{%o16} 0.5\]

(%i18) mG1:(x−x1)·G1;mG2:(x−x2)·G2;

\[\]\[\tag{%o17} 17\]

\[\]\[\tag{%o18} 22\]

(%i20) L:(mG1+mG2)/G,numer;L_3:L·1000;

\[\]\[\tag{%o19} 13\]

\[\]\[\tag{%o20} 13000\]

(%i21) L:(floor(L_3))/1000,numer;

\[\]\[\tag{%o21} 13\]

(%i22) label_L:sconcat(L);

\[\]\[\tag{%o22} "13"\]

(%i23) fL(x1,x2,G1,G2):=(x1·G1+x2·G2)/(G1+G2);

\[\]\[\tag{%o23} \mathop{fL}\left( \ensuremath{\mathrm{x1}}\mathop{,}\ensuremath{\mathrm{x2}}\mathop{,}\ensuremath{\mathrm{G1}}\mathop{,}\ensuremath{\mathrm{G2}}\right) \mathop{:=}\frac{\ensuremath{\mathrm{x1}}\, \ensuremath{\mathrm{G1}}\mathop{+}\ensuremath{\mathrm{x2}}\, \ensuremath{\mathrm{G2}}}{\ensuremath{\mathrm{G1}}\mathop{+}\ensuremath{\mathrm{G2}}}\]

(%i24) fL((x−x1),(x−x2),G1,G2),numer;

\[\]\[\tag{%o24} 13\]

(%i27) L1:x−x1;L2:x−x2;L;

\[\]\[\tag{%o25} 17\]

\[\]\[\tag{%o26} 11\]

\[\]\[\tag{%o27} 13\]

(%i28) kill(sW,sU,sS);

\[\]\[\tag{%o28} \ensuremath{\mathrm{done}}\]

(%i29) sW:[G1,G2,G,x1,x2,x,L1,L2,L];

\[\]\[\tag{%o29} \left[ 1\mathop{,}2\mathop{,}3\mathop{,}\mathop{-}5\mathop{,}1\mathop{,}12\mathop{,}17\mathop{,}11\mathop{,}13\right] \]

(%i30) sS:['G1,'G2,'G,'x1,'x2,'x,'L1,'L2,'L];

\[\]\[\tag{%o30} \left[ \ensuremath{\mathrm{G1}}\mathop{,}\ensuremath{\mathrm{G2}}\mathop{,}G\mathop{,}\ensuremath{\mathrm{x1}}\mathop{,}\ensuremath{\mathrm{x2}}\mathop{,}x\mathop{,}\ensuremath{\mathrm{L1}}\mathop{,}\ensuremath{\mathrm{L2}}\mathop{,}L\right] \]

(%i31) sU:['N,'N,'N,'m,'m,'m,'m,'m,'m];

\[\]\[\tag{%o31} \left[ N\mathop{,}N\mathop{,}N\mathop{,}m\mathop{,}m\mathop{,}m\mathop{,}m\mathop{,}m\mathop{,}m\right] \]

(%i33) size1:sqrt(G1),numer;size2:sqrt(G2),numer;

\[\]\[\tag{%o32} 1.0\]

\[\]\[\tag{%o33} 1.4142135623730951\]

(%i34) del1:0.5;

\[\]\[\tag{%o34} 0.5\]

(%i36) draw2d(xrange = [x1−2,x+4],
yrange = [−5,6],
 font      = "Arial",
           font_size = 30,
title="jh_k123_momentForce.wxmx",
 grid = true,
 proportional_axes=xy,
line_width=4,color=black,
   fill_color = "#eeeeee",
    rectangle([−size1/2+x1,−size1/2],[size1/2+x1,size1/2]),
    rectangle([−size2/2+x2,−size2/2],[size2/2+x2,size2/2]),
     points_joined = false,
    color=red,
   point_size=1,
   line_width=1.3,
   line_type = solid,
point_type = filled_circle,
points([[x1,0],[x2,0],[x,0],[(x−L),4]]),
    label([fstr3(sW[1],sS[1],sU[1]),x1,−size1/2−del1]),
     label([fstr3(sW[2],sS[2],sU[2]),x2,−size2/2−del1]),
     points_joined = true,
   point_size=0.1,
   line_width=1.3,
   line_type = solid,
points([[x1,0],[x1,4],[x2,4],[x2,0],[x2,4],[x,4],[x,0]]),
     line_type = solid,
   color=black,line_width=1,
   head_both = true,
   head_length = 0.4,
   head_angle = 10,
vector([x1,−4],[(x−x1),0]),
    label([fstr3(sW[7],sS[7],sU[7]),(x−x1)/2,−4+del1]),
    vector([x2,−3],[(x−x2),0]),
    label([fstr3(sW[8],sS[8],sU[8]),(x−x2)/2+x2,−3+del1]),
    color=red,
    vector([(x−L),3],[L,0]),
    label([fstr3(sW[9],sS[9],sU[9]),(x−L/2),3+del1]),
    head_both = false,
     vector([(x−L),4],[0,3·del1]),
    label([fstr_sum(sW[3],sS[3],sU[3],G1,G2),(x−L),4.5]),
      /*  GPL */
font      = "Arial",
           font_size = 16,
 color = "#0e406e",
label_orientation = 'vertical,
label(["www.k123.org.ua ",12,1.3]),
 label(["Kopanytsia Y (c)  2025",12.5,1.3])
   )$
Figure 1:
Diagram

Variants 2

(%i37) kill(all);

\[\]\[\tag{%o0} \ensuremath{\mathrm{done}}\]

(%i6) G1:1;G2:6;L1:0;L2:8;G:G1+G2;L:13;

\[\]\[\tag{%o1} 1\]

\[\]\[\tag{%o2} 6\]

\[\]\[\tag{%o3} 0\]

\[\]\[\tag{%o4} 8\]

\[\]\[\tag{%o5} 7\]

\[\]\[\tag{%o6} 13\]

(%i8) mG1:(L−L1)·G1;mG2:(L−L2)·G2;

\[\]\[\tag{%o7} 13\]

\[\]\[\tag{%o8} 30\]

(%i9) L:(mG1+mG2)/G,numer;

\[\]\[\tag{%o9} 6.142857142857143\]

(%i10) label_L:sconcat(L);

\[\]\[\tag{%o10} "6.142857142857143"\]

(%i11) fL(L1,L2,G1,G2):=(L1·G1+L2·G2)/(G1+G2);

\[\]\[\tag{%o11} \mathop{fL}\left( \ensuremath{\mathrm{L1}}\mathop{,}\ensuremath{\mathrm{L2}}\mathop{,}\ensuremath{\mathrm{G1}}\mathop{,}\ensuremath{\mathrm{G2}}\right) \mathop{:=}\frac{\ensuremath{\mathrm{L1}}\, \ensuremath{\mathrm{G1}}\mathop{+}\ensuremath{\mathrm{L2}}\, \ensuremath{\mathrm{G2}}}{\ensuremath{\mathrm{G1}}\mathop{+}\ensuremath{\mathrm{G2}}}\]

(%i12) fL((L−L1),(L−L2),G1,G2),numer;

\[\]\[\tag{%o12} \mathop{-}0.7142857142857139\]

(%i14) size1:sqrt(G1),numer;size2:sqrt(G2),numer;

\[\]\[\tag{%o13} 1.0\]

\[\]\[\tag{%o14} 2.449489742783178\]

(%i15) del1:0.5;

\[\]\[\tag{%o15} 0.5\]

(%i16) draw2d(xrange = [−2,14],
yrange = [−5,6],
 font      = "Arial",
           font_size = 30,
title="jh_k123_momentForce.wxmx",
 grid = true,
 proportional_axes=xy,
line_width=4,color=black,
   fill_color = "#eeeeee",
rectangle([−size1/2+L1,−size1/2+L1],[size1/2+L1,size1/2+L1]),
    rectangle([−size2/2+L2,−size2/2],[size2/2+L2,size2/2]),
     points_joined = false,
    color=red,
   point_size=1,
   line_width=1.3,
   line_type = solid,
point_type = filled_circle,
points([[L1,0],[L2,0],[L,0],[L,4]]),
    label(["G1=+1",L1,−size1/2−del1]),
     label(["G2=+6",L2,−size2/2−del1]),
     points_joined = true,
   point_size=0.1,
   line_width=1.3,
   line_type = solid,
points([[L1,0],[L1,4],[L2,4],[L2,0],[L2,4],[L,4],[L,0]]),
     line_type = solid,
   color=black,line_width=1,
   head_both = true,
   head_length = 0.4,
   head_angle = 10,
vector([L1,−4],[(L−L1),0]),
    label(["L1",(L−L1)/2,−4+del1/2]),
    vector([L2,−3],[(L−L2),0]),
    label(["L2",(L−L2)/2+L2,−3+del1/2]),
    color=red,
    vector([L,3],[(L−L),0]),
    label(["L=?",(L−L)/2+L,3+del1]),
    head_both = false,
     vector([L,4],[0,3·del1]),
    label(["G=G1+G2",L,4.5]),
      /*  GPL */
font      = "Arial",
           font_size = 16,
 color = "#0e406e",
label_orientation = 'vertical,
label(["www.k123.org.ua ",12,1.3]),
 label(["Kopanytsia Y (c)  2025",12.5,1.3])
   )$
Figure 2:
Diagram
(%i17) kill(all);

\[\]\[\tag{%o0} \ensuremath{\mathrm{done}}\]

(%i6) G1:1;G2:6;L1:0.5;L2:8.9;G:G1+G2;L:−1;

\[\]\[\tag{%o1} 1\]

\[\]\[\tag{%o2} 6\]

\[\]\[\tag{%o3} 0.5\]

\[\]\[\tag{%o4} 8.9\]

\[\]\[\tag{%o5} 7\]

\[\]\[\tag{%o6} \mathop{-}1\]

(%i8) mG1:(L1+L)·G1;mG2:(L2+L)·G2;

\[\]\[\tag{%o7} \mathop{-}0.5\]

\[\]\[\tag{%o8} 47.400000000000006\]

(%i9) L3:(mG1+mG2)/G,numer;

\[\]\[\tag{%o9} 6.700000000000001\]

(%i10) fL(L1,L2,G1,G2):=(L1·G1+L2·G2)/(G1+G2);

\[\]\[\tag{%o10} \mathop{fL}\left( \ensuremath{\mathrm{L1}}\mathop{,}\ensuremath{\mathrm{L2}}\mathop{,}\ensuremath{\mathrm{G1}}\mathop{,}\ensuremath{\mathrm{G2}}\right) \mathop{:=}\frac{\ensuremath{\mathrm{L1}}\, \ensuremath{\mathrm{G1}}\mathop{+}\ensuremath{\mathrm{L2}}\, \ensuremath{\mathrm{G2}}}{\ensuremath{\mathrm{G1}}\mathop{+}\ensuremath{\mathrm{G2}}}\]

(%i11) fL((L−L1),(L−L2),G1,G2),numer;

\[\]\[\tag{%o11} \mathop{-}8.700000000000001\]

(%i13) size1:sqrt(G1),numer;size2:sqrt(G2),numer;

\[\]\[\tag{%o12} 1.0\]

\[\]\[\tag{%o13} 2.449489742783178\]

(%i14) del1:0.5;

\[\]\[\tag{%o14} 0.5\]

(%i15) draw2d(xrange = [−2,14],
yrange = [−5,6],
 font      = "Arial",
           font_size = 30,
title="jh_k123_momentForce.wxmx",
 grid = true,
 proportional_axes=xy,
line_width=4,color=black,
   fill_color = "#eeeeee",
rectangle([−size1/2+L1,−size1/2+L1],[size1/2+L1,size1/2+L1]),
    rectangle([−size2/2+L2,−size2/2],[size2/2+L2,size2/2]),
     points_joined = false,
    color=red,
   point_size=1,
   line_width=1.3,
   line_type = solid,
point_type = filled_circle,
points([[L1,0],[L2,0],[L,0],[L3,4]]),
    label(["G1=+1",L1,−size1/2−del1]),
     label(["G2=+6",L2,−size2/2−del1]),
     points_joined = true,
   point_size=0.1,
   line_width=1.3,
   line_type = solid,
points([[L1,0],[L1,4],[L2,4],[L2,0],[L2,4],[L,4],[L,0]]),
     line_type = solid,
   color=black,line_width=1,
   head_both = true,
   head_length = 0.4,
   head_angle = 10,
vector([L1,−4],[(L−L1),0]),
    label(["L1",(L−L1)/2,−4+del1/2]),
    vector([L2,−3],[(L−L2),0]),
    label(["L2",(L−L2)/2+L2,−3+del1/2]),
    color=red,
    vector([L3,3],[(L−L3),0]),
    label(["L3=?",(L−L3)/2+L3,3+del1]),
    head_both = false,
     vector([L3,4],[0,3·del1]),
    label(["G=G1+G2",L3,4.5]),
      /*  GPL */
font      = "Arial",
           font_size = 16,
 color = "#0e406e",
label_orientation = 'vertical,
label(["www.k123.org.ua ",12,1.3]),
 label(["Kopanytsia Y (c)  2025",12.5,1.3])
   )$
Figure 3:
Diagram

Created with wxMaxima.

The source of this Maxima session can be downloaded here.