(3+2√2)(3−2√2)=3^2-(2√2)^2=9-8=1
3(√3−1)^2−(3√2＋1)(3√2−1)=3(√3−1)^2−{(3√2)^2−1^2}=3(√3−1)^2−17
=3(3-2√3+1)−17=-(5+6√3)