4 4 * √2 4 * √2 4 * √ 2 4 * √ 2 * ( √ 5 - 1 )
------------- = ------------------ = ---------------- = ----------- = --------------------------- =
√ (√5 + 3) √ (6 + 2 * √ 5) √ (1 + √ 5 )² √ 5 + 1 ( √ 5 + 1) * ( √ 5 - 1 )
= √ 2 * ( √ 5 - 1) = √ 10 - √ 2