1.(x^2+2xy+y^2)(x^2-xy+y^2)^2=（x+y）^2(x^2-xy+y^2)^2=[(x+y)(x^2-xy+y^2)]^2=[(x+y)^3]^2=(x+y)^6
2.答案复杂,不好写,方法是x^3+1/X^3=（x+1/x）(x^2-1+1/x^2)
x^2-3x-1=0推出x-3-1/x=0推出x-1/x=3推出(x-1/x)^2=3^2得到x^2+1/x^2-2=9
再代入上式,计算
3.看不懂题目
1.(x^2+2xy+y^2)(x^2-xy+y^2)^2=（x+y）^2(x^2-xy+y^2)^2=[(x+y)(x^2-xy+y^2)]^2=[(x+y)^3]^2=(x+y)^6
2.答案复杂,不好写,方法是x^3+1/X^3=（x+1/x）(x^2-1+1/x^2)
x^2-3x-1=0推出x-3-1/x=0推出x-1/x=3推出(x-1/x)^2=3^2得到x^2+1/x^2-2=9
再代入上式,计算
3.看不懂题目