X^3-6X^2+9X-5=0求解,

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X^3-6X^2+9X-5=0求解,X^3-6X^2+9X-5=0求解,X^3-6X^2+9X-5=0求解,X1=4.10380340273554X2=0.948098298632232-0.5652

X^3-6X^2+9X-5=0求解,
X^3-6X^2+9X-5=0求解,

X^3-6X^2+9X-5=0求解,
X1=4.10380340273554
X2=0.948098298632232-0.565235851677171i
X3=0.948098298632232+0.565235851677171i

让f(x) = x^3-6x^2 +9x-5
f'(x) = 3x^2 - 12x + 9
3x^2 - 12x + 9 = 0
3(x-1)(x-3) = 0
x = 1 or x = 3
f(1) = -1, f(3) = -5
∴方程的解为-1 , -5很抱歉,谢谢你的回答,方程的解肯定不是负数。好的,我再看看,貌似我用函数求导的方法是不行的....

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让f(x) = x^3-6x^2 +9x-5
f'(x) = 3x^2 - 12x + 9
3x^2 - 12x + 9 = 0
3(x-1)(x-3) = 0
x = 1 or x = 3
f(1) = -1, f(3) = -5
∴方程的解为-1 , -5

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