reserve X for set;
reserve a,b,c,k,m,n for Nat;
reserve i,j for Integer;
reserve r,s for Real;
reserve p,p1,p2,p3 for Prime;

theorem Th96:
  for r being Complex st r <> 0 holds 2*(7/r)|^3 + 7/r*(r-98/r^2) - 7 = 0
  proof
    let r be Complex;
    assume
A1: r <> 0;
A2: (7/r)|^3 = (7/r)*(7/r)*(7/r) by POLYEQ_5:2
    .= 343*(r"*r"*r")
    .= 343*((r*r)"*r") by XCMPLX_1:204
    .= 343/(r*r*r) by XCMPLX_1:204;
A3: 7/r*r = 7 by A1,XCMPLX_1:87;
    7/r*(98/r^2) = 686*(r"*(r*r)")
    .= 686/(r*r*r) by XCMPLX_1:204;
    hence thesis by A2,A3;
  end;
