symsr1r2r3av;A=[-r10-100;r1+r2-r2000;-r2r2+r3010;1000-1;0100a];B=[000v0];x=A\B之后就报错了E... syms r1 r2 r3 a v;
A=[-r1 0 -1 0 0;r1+r2 -r2 0 0 0;-r2 r2+r3 0 1 0;1 0 0 0 -1;0 1 0 0 a];
B=[0 0 0 v 0];
x=A\B
之后就报错了
Error using mupadmex
Error in MuPAD command: Operands are invalid. [linalg::matlinsolve]

Error in sym/privBinaryOp (line 1506)
Csym = mupadmex(op,args{1}.s, args{2}.s, varargin{:});

Error in sym/mldivide (line 249)
X = privBinaryOp(A, B, 'symobj::mldivide');