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#1 2012-10-19 19:49:48

Harold
Guest

Cubic equation

How do i solve a equation of this form ax^3+bx^2+cx+d=0 is there a formula?please explain

#2 2012-10-19 20:34:50

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 105,318

Re: Cubic equation

Hi Harold;

Yes, there is a formula but no one ever uses it.


In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
No great discovery was ever made without a bold guess.

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#3 2012-10-19 20:45:15

zetafunc.
Guest

Re: Cubic equation

It would be helpful to remember but you're unlikely to use it very often. Try to find the first by inspection (or iteration if you have a calculator), then determine the quadratic factor from there.

#4 2012-10-19 20:53:55

bob bundy
Moderator
Registered: 2010-06-20
Posts: 7,651

Re: Cubic equation


Children are not defined by school ...........The Fonz
You cannot teach a man anything;  you can only help him find it within himself..........Galileo Galilei

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#5 2012-10-20 08:32:14

bobbym
Administrator
From: Bumpkinland
Registered: 2009-04-12
Posts: 105,318

Re: Cubic equation

Or one even nastier than that.

http://www.mathisfunforum.com/viewtopic … 00#p198900

See post#6.


In mathematics, you don't understand things. You just get used to them.
If it ain't broke, fix it until it is.
No great discovery was ever made without a bold guess.

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