theorem Th43:
  for r being Element of F_Real holds power(r,n) = ( #Z n).r
  proof
    let r be Element of F;
    thus power(r,n) = 1.F * power(r,n)
    .= FPower(1.F,n).r by POLYNOM5:def 12
    .= ( #Z n).r by Th40;
  end;
