解方程:x3-3x-2=0

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解方程:x3-3x-2=0
解方程:x3-3x-2=0

解方程:x3-3x-2=0
x3-2x-x-2=0
x(x2-1)-2(x+1)=0
x(x+1)(x-1)-2(x+1)=0
(x+1)(x2-x-2)=0
(x+1)2(x-2)=0
x=2或者x=-1

额,x3是3x吧
3x-3x-2=0
-2=0
所以x无解

x无解
要是x3为x^3,那{{x -> -(1/(1 + Sqrt[2])^(1/3)) + (1 + Sqrt[2])^(
1/3)}, {x -> -(1/2) (1 + Sqrt[2])^(1/3) (1 - I Sqrt[3]) + (
1 + I Sqrt[3])/(2 (1 + Sqrt[2])^(1/3))}, {x -> (1 - I Sqrt[3])/(
2 (1 + Sqrt[2])^(1/3)) - 1/2 (1 + Sqrt[2])^(1/3) (1 + I Sqrt[3])}}
软件解得