- $\displaystyle x^3-3x-1=0$
- $\displaystyle x^3+x^2-2x-1=0$

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- Feb 3rd 2010, 12:20 AMjames_bondSolve 2 cubic equations
- $\displaystyle x^3-3x-1=0$
- $\displaystyle x^3+x^2-2x-1=0$

- Feb 3rd 2010, 01:24 AMmr fantastic
- Feb 3rd 2010, 11:30 PMjames_bond
I have to give the explicit answer not just numerical approximation. I can use whatever I know/find not just Cardano's method. Using Mathematica I've found 2 solutions to the first equation: $\displaystyle 2\cos\left[\frac {\pi}9\right]$ and $\displaystyle -\cos\left[\frac {\pi}9\right]+\sqrt 3\sin\left[\frac {\pi}9\right]$. Waiting for ideas...