计算二次根式,

问题描述:

计算二次根式,
(根号5+根号2-1)(5-根号10+根号5)

(根号5+根号2-1)(5-根号10+根号5)
=根号5[根号5+(根号2-1)][根号5-(根号2-1)]
=根号5[5-(根号2-1)平方]
=根号5(5-2+2根号2-1)
=根号5(2+2根号2
=2根号5+2根号10