Consider:
√2, √3, √5, √6
= √(16 x 5)
= √16 x √5
= 4√5
= (3 + 4 - 5)√2
= 2√2
= 5 x √4 x √2 - 2√
= 5 x 2 x √2 - 2√2
= 10√2 - 2√2
= (10 - 2)√2
= 8√2