解;(2根号3+3根号2-6)(2根号3-3根号2+根号6)
=[2根号3+(3根号2-根号6)][2根号3-(3根号2-根号6)]
=(2根号3)^2-(3根号2-根号6)^2
=12-(18+6-6根号12)
-12+12根号3