已知x+1/x=2,x^2+1/x^2=3,求x^3+1/x^3的值

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已知x+1/x=2,x^2+1/x^2=3,求x^3+1/x^3的值已知x+1/x=2,x^2+1/x^2=3,求x^3+1/x^3的值已知x+1/x=2,x^2+1/x^2=3,求x^3+1/x^3

已知x+1/x=2,x^2+1/x^2=3,求x^3+1/x^3的值
已知x+1/x=2,x^2+1/x^2=3,求x^3+1/x^3的值

已知x+1/x=2,x^2+1/x^2=3,求x^3+1/x^3的值
x^3+1/x^3
=(x+1/x)(x^2-1+1/x^2)
=2×(3-1)
=4.

题目表达不清,是不是(x+1)/x=2,(x^2+1)/x^2=3,求(x^3+1)/x^3的值
如果是这样x^3+1/x^3
=(x+1/x)(x^2-1+1/x^2)
=2×(3-1)
=4.
那么:x+1/x=2,两边同时平方,x^2+2+1/x^2=4 x^2+1/x^2=2与x^2+1/x^2=3有矛盾。