Empty 0-by-1 when using solve:
1 view (last 30 days)
Show older comments
syms x1 x2 x3 x4 x5 x6 x7 x8 x9
eqt1=x1+1600*x2+1600^2*x3+(x4+1600*x5+1600^2*x6)*50+(x7+1600*x8*1600^2*x9)*50^2==260;
eqt2=x1+1600*x2+1600^2*x3+(x4+1600*x5+1600^2*x6)*100+(x7+1600*x8*1600^2*x9)*100^2==55;
eqt3=x1+1600*x2+1600^2*x3+(x4+1600*x5+1600^2*x6)*200+(x7+1600*x8*1600^2*x9)*200^2==30;
eqt4=x1+1300*x2+1300^2*x3+(x4+1300*x5+1300^2*x6)*50+(x7+1300*x8*1300^2*x9)*50^2==40;
eqt5=x1+1300*x2+1300^2*x3+(x4+1300*x5+1300^2*x6)*100+(x7+1300*x8*1300^2*x9)*100^2==36;
eqt6=x1+1300*x2+1300^2*x3+(x4+1300*x5+1300^2*x6)*200+(x7+1300*x8*1300^2*x9)*200^2==15;
eqt7=x1+1100*x2+1100^2*x3+(x4+1100*x5+1100^2*x6)*50+(x7+1100*x8*1100^2*x9)*50^2==21;
eqt8=x1+1100*x2+1100^2*x3+(x4+1100*x5+1100^2*x6)*100+(x7+1100*x8*1100^2*x9)*100^2==17;
eqt9=x1+1100*x2+1100^2*x3+(x4+1100*x5+1100^2*x6)*200+(x7+1100*x8*1100^2*x9)*200^2==3;
sol=solve([eqt1,eqt2,eqt3,eqt4,eqt5,eqt6,eqt7,eqt8,eqt9],[x1,x2,x3,x4,x5,x6,x7,x8,x9])
a1=sol.x1
1 Comment
Star Strider
on 7 Dec 2019
There does not appear to be a unique solution:
syms x1 x2 x3 x4 x5 x6 x7 x8 x9
eqt1=x1+1600*x2+1600^2*x3+(x4+1600*x5+1600^2*x6)*50+(x7+1600*x8*1600^2*x9)*50^2-260;
eqt2=x1+1600*x2+1600^2*x3+(x4+1600*x5+1600^2*x6)*100+(x7+1600*x8*1600^2*x9)*100^2-55;
eqt3=x1+1600*x2+1600^2*x3+(x4+1600*x5+1600^2*x6)*200+(x7+1600*x8*1600^2*x9)*200^2-30;
eqt4=x1+1300*x2+1300^2*x3+(x4+1300*x5+1300^2*x6)*50+(x7+1300*x8*1300^2*x9)*50^2-40;
eqt5=x1+1300*x2+1300^2*x3+(x4+1300*x5+1300^2*x6)*100+(x7+1300*x8*1300^2*x9)*100^2-36;
eqt6=x1+1300*x2+1300^2*x3+(x4+1300*x5+1300^2*x6)*200+(x7+1300*x8*1300^2*x9)*200^2-15;
eqt7=x1+1100*x2+1100^2*x3+(x4+1100*x5+1100^2*x6)*50+(x7+1100*x8*1100^2*x9)*50^2-21;
eqt8=x1+1100*x2+1100^2*x3+(x4+1100*x5+1100^2*x6)*100+(x7+1100*x8*1100^2*x9)*100^2-17;
eqt9=x1+1100*x2+1100^2*x3+(x4+1100*x5+1100^2*x6)*200+(x7+1100*x8*1100^2*x9)*200^2-3;
eqt1 = simplify(eqt1, 'Steps', 250);
eqt2 = simplify(eqt2, 'Steps', 250);
eqt3 = simplify(eqt3, 'Steps', 250);
eqt4 = simplify(eqt4, 'Steps', 250);
eqt5 = simplify(eqt5, 'Steps', 250);
eqt6 = simplify(eqt6, 'Steps', 250);
eqt7 = simplify(eqt7, 'Steps', 250);
eqt8 = simplify(eqt8, 'Steps', 250);
eqt9 = simplify(eqt9, 'Steps', 250);
% sol=vpasolve([eqt1,eqt2,eqt3,eqt4,eqt5,eqt6,eqt7,eqt8,eqt9],[x1,x2,x3,x4,x5,x6,x7,x8,x9])
% a1=sol.x1
eqtfcn = matlabFunction([eqt1,eqt2,eqt3,eqt4,eqt5,eqt6,eqt7,eqt8,eqt9], 'Vars',{[x1,x2,x3,x4,x5,x6,x7,x8,x9]})
soln = fsolve(eqtfcn, ones(1,9))
Answers (1)
Walter Roberson
on 8 Dec 2019
The equations are inconsistent. If you solve the first 7 equations for [x1, x2, x3, x4, x5, x7, x8], and substitute those in to the 8th and 9th equations, then you end up with
[366349/1899 + 5000000*x6 = 17, 649934/1899 + 15000000*x6 = 3]
which is inconsistent.
0 Comments
See Also
Categories
Find more on Calculus in Help Center and File Exchange
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!