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问题: .1.(1)x=√(5+√5),y=√(5-√5) ,

1.(1)x=√(5+√5),y=√(5-√5)
(2)(x+1)^2+√(y-2√2)=0
证明:
(1)==〉x^6+y^6=400
(2)=/=〉x^6+y^6=400

解答:

(1)x=√(5+√5),y=√(5-√5)
证明:x^6+y^6=400
x^+y^=10
xy=√20
x^6+y^6=(x^+y^)[x^4-(xy)^+y^4]
=10[(x^+y^)^-3(xy)^]=400
(2)(x+1)^2+√(y-2√2)=0
证明:
(2)=/=〉x^6+y^6=400
∵ (x+1)^2 ≥0 √(y-2√2)≥0
(x+1)^2+√(y-2√2)=0
∴(x+1)^2 =0 x=-1
√(y-2√2)=0 y=2√2
x^6+y^6=1+512=513≠400