1、√78-√9/5+√27 =√78-3√5/5+3√3
2、(√72)/(1/1的3次方*√12)=6√2 /(1/2√3)=12√6
3、|√6+√2|+|√2-1|-|3-√6|
=√6+√2+√2-1-(3-√6)
=2√6+2√2-4