如何解一元三次方程式一般式？

来源：百度知道 编辑：UC知道 时间：2024/05/26 17:22:31
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卡当公式
{{x -> -(b/(
3 a)) - (2^(
1/3) (-b^2 + 3 a c))/(3 a (-2 b^3 + 9 a b c - 27 a^2 d + Sqrt[
4 (-b^2 + 3 a c)^3 + (-2 b^3 + 9 a b c - 27 a^2 d)^2])^(
1/3)) + (-2 b^3 + 9 a b c - 27 a^2 d + Sqrt[
4 (-b^2 + 3 a c)^3 + (-2 b^3 + 9 a b c - 27 a^2 d)^2])^(1/3)/(
3 2^(1/3) a)}, {x -> -(b/(
3 a)) + ((1 + I Sqrt[3]) (-b^2 + 3 a c))/(3 2^(2/3)
a (-2 b^3 + 9 a b c - 27 a^2 d + Sqrt[
4 (-b^2 + 3 a c)^3 + (-2 b^3 + 9 a b c - 27 a^2 d)^2])^(
1/3)) - (1/(
6 2^(1/3)
a))(1 - I Sqrt[3]) (-2 b^3 + 9 a b c - 27 a^2 d + Sqrt[
4 (-b^2 + 3 a c)^3 + (-2 b^3 + 9 a b c - 27 a^2 d)^2])^(
1/3)}, {x -> -(b/(
3 a)) + ((1 - I Sqrt[3]) (-b^2 + 3 a c))/(3 2^(2/3)
a (-2 b^3 + 9 a b c - 27 a^2 d + Sqrt[
4 (-b^2 + 3 a c)^3 + (-2 b^3 + 9 a b c - 27 a^2 d)^2])^(
1/3)) - (1/(
6 2^(1/3)