some help please-optimization method using (QUADPROG)instruction

hello
I tried to program a cost function of optimization technique using
('QUADPROG' instruction such that [x]=QUADPROG(H,f,A,b,bl) ) I used
sum of squares cost function G(x)=Σ(xi/A)2 subjected to x=A-1b,
where xi (i=1....9)are forces but I had error in because matrix A
(3*9) has not the same length with vector b(3*1) ,and I did not yet
know how to find f and H from the cost function equation .Could you
please tell me how to overcome this error and how to find H and f?

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