&*** (20 9:44:5)1／χ+χ=3,则χ4+χ²+1／χ²=?_数学解答

&*** (20 9:44:5)
1／χ+χ=3,则χ4+χ²+1／χ²=?

人气：366 ℃　时间：2020-04-12 05:47:04

解答

(x^4+x^2+1)/x^2
=x^2 +1/x^2 +1
=x^2 +1/x^2+2 -1
=(x+ 1/x)^2-1
=3^2-1
=8

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