x=(√3-√2)/(√3+√2),y=(√3+√2)/(√3-√2),xy=1/1=1x²-y²=(5-2√6)/(5+2√6)-(5+2√6)/(5-2√6)=【(5-2√6)²-(5+2√6)²】/(25-24)=-40√6所以3x^2-5xy-3y^2=3x^2-3y^2-5xy=3×（-40√6）-5=-120√6-5
-120√6-5
