(根号7+2-2根号3)(根号7-2+2根号3)

问题描述:

(根号7+2-2根号3)(根号7-2+2根号3)

=[√7+(2-2√3)][√7-(2-2√3)]
=(√7)²-(2-2√3) ²
=7-(4-8√3+12)
=8√3 -9