已知x=√3+√2,y=√3-√2,求x^2-xy+y^2与x^3y+xy^3的值.

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已知x=√3+√2,y=√3-√2,求x^2-xy+y^2与x^3y+xy^3的值.

已知x=√3+√2,y=√3-√2,求x^2-xy+y^2与x^3y+xy^3的值.
已知x=√3+√2,y=√3-√2,求x^2-xy+y^2与x^3y+xy^3的值.

已知x=√3+√2,y=√3-√2,求x^2-xy+y^2与x^3y+xy^3的值.
x+y=2√3
xy=1
∴x²-xy+y²=(x+y)²-3xy=12-3=9
x³y+xy³=xy(x²+y²)=xy[(x+y)²-2xy]=12-2=10

x^2-xy+y^2=(x-y)^2+xy=8+1=9
x^3y+xy^3=xy(x^2+y^2)=xy[(x-y)^2+2xy]=8+2=10

x^2-xy+y^2
=(x-y)^2+xy
=(√3+√2-√3+√2)^2+(√3+√2)(√3-√2)
=8+1
=9
x^3y+xy^3
=xy(x^2+y^2)
=(√3+√2)^2+(√3-√2)^2
=(3+2√6+2)+(3-2√6+2)
=3+2√6+2+3-2√6+2
=10