a-b=3+2;a的平方+b的平方-2ab=5+2倍根号6b-c=3-2;b的平方+c的平方-2bc=1-2倍根号6ab-b的平方-ac+bc=1所以三个式子相加得出结果是7
∵a-b=√3+√2 b-c=√3-√2 ∴a-c=(a-b)+(b-c)=2√3a�0�5+b�0�5+c�0�5-ab-bc-ca=1/2(2a�0�5+2b�0�5+2c�0�5-2ab-2bc-2ca)=1/2×【(a�0�5-2ab+b�0�5)+(a�0�5-2ca+c�0�5)+(b�0�5-2bc-c�0�5)】=1/2×【(a-b)�0�5+(a-c)�0�5+(b-c)�0�5】=1/2×【(√3+√2)�0�5+(2√3)�0�5+(√3-√2)�0�5】=1/2×【(5+2√6)+12+(5-2√6)】=1/2×22=11