reserve a, b, c, d, e for Complex;

theorem Th117: :: REAL_2'96
  a <> 0 implies a + b = a * (1 + b / a)
proof
  assume
A1: a<>0;
  hence a+b=a*(a/a+b/a) by Th114
    .=a*(1+b/a) by A1,Lm5;
end;
