reserve i,j,m,n,k for Nat,
  x,y for set,
  K for Field,
  a,L for Element of K;

theorem Th2:
  Det Jordan_block(L,n) = power(K).(L,n)
proof
  thus Det Jordan_block(L,n)=(the multF of K)$$ diagonal_of_Matrix
  Jordan_block(L,n) by MATRIX13:7
    .= Product(n|->L) by Th1
    .= power(K).(L,n) by MATRIXJ1:5;
end;
