Thread: Derive the Cubic formula
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Old April 20th, 2008, 06:28 AM
ice_syncer ice_syncer is offline
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Quote:
Originally Posted by topsquark View Post
If you are serious about this, try Cardano's method.

-Dan
Yeah well, I saw read that article before I posted it,
anyways I did derive a formula by "completing the cube" method, just took 5 minutes, sadly it only works for perfect cubes or cubic equations with one root.

It is [-b+ CUBEROOT(-27a^2d+b^3)]/3a

-27a^2d+b^3 is the discriminant, funny part is, the discriminant is always 0 so the actual formula is -b/3a.


Ice SYnc
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