Is there a specific way of solving cubic equations, apart from guessing factors?

Question

anonymous · Answer

what do u mean by guessing factors

anonymous · Answer

$$as \in if you want \to solve -x^{3}+12x+16, you try (x-1),(x-2) etc$$

anonymous · Answer

Cardano's formula ...

mertsj · Answer

The possible rational roots are the factors of the constant term divided by the factors of the coefficient of the cubic term.  Use synthetic division to see if any of those numbers are roots.

anonymous · Answer

woah Cardano's method seems complicated

mertsj · Answer

Just do what I said.  It is pretty easy.

anonymous · Answer

ok let me try that...Thanks

mertsj · Answer

If you post an equation I could help you.

anonymous · Answer

yeah ok let me do that

anonymous · Answer

$$-x ^{3}+12x+16=0$$

mertsj · Answer

Possible rational roots:

$$\pm1, \pm2,\pm 4, \pm8, \pm16$$

anonymous · Answer

ok so how did you get those numbers?

anonymous · Answer

ow so the factors of 12 and the factors of 16

anonymous · Answer

yeah I get it

mertsj · Answer

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