code: def _to_power_basis11(nodes1, nodes2):
      r
      # We manually invert the Vandermonde matrix:
      # [1 0][c0] = [n0]
      # [1 1][c1]   [n1]
      val0 = eval_intersection_polynomial(nodes1, nodes2, 0.0)
      val1 = eval_intersection_polynomial(nodes1, nodes2, 1.0)
      # [c0] = [ 1 0][n0]
      # [c1] = [-1 1][n1]
      return np.asfortranarray([val0, -val0 + val1])
docs: r"""Compute the coefficients of an **intersection polynomial**.
  
      Helper for :func:`to_power_basis` in the case that each curve is
      degree one. In this case, B |eacute| zout's `theorem`_ tells us
      that the **intersection polynomial** is degree :math:`1 \cdot 1`
      hence we return two coefficients.
  
      Args:
          nodes1 (numpy.ndarray): The nodes in the first curve.
          nodes2 (numpy.ndarray): The nodes in the second curve.
  
      Returns:
          numpy.ndarray: ``2``-array of coefficients.