reserve i,j for Element of NAT,
  x,y,z for FinSequence of COMPLEX,
  c for Element of COMPLEX,
  R,R1,R2 for Element of i-tuples_on COMPLEX;

theorem Th35:
  for c being Complex holds -c*x = c*(-x)
proof
  let c be Complex;
A1: len (c*(-x))=len (-x) & len (c*x)=len x by Th3;
A2: len x=len (-x) by Th5;
  then c*(-x) + c*x = c*(x+-x) by Th25
    .= c*(0c (len x)) by Th28
    .= 0c (len x) by Th34;
  hence thesis by A2,A1,Th26;
end;
