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#1 2014-06-26 02:29:02

UKjames
Member
Registered: 2014-06-26
Posts: 1

Factoring x^3-3x^2+x=0

Out of curiosity, i'm attempting to factor the following equation x^3-3x^2+x=0

I decided upon using the Greatest Common Factor method, and factor out x, giving me the following:

x(x^2-3x+1)=0,  thereby making my first factor x=0.

I recognised the equation in the bracket is of the quadratic form, so i ran it through an online quadratic calculator to get the remaining two factors.

However after running the original equation through google graphs I noticed that, barring x=0, none of the factors/roots match those given by the quadratic calculator.

Is anyone able to explain why?

NB: Please be gentle! I realise i've probably have made a really silly, elementary mistake!

Ignore the above message. I realised my mistake!! And it was embarrassingly elementary!!

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#2 2014-06-30 00:03:16

Nehushtan
Member
Registered: 2013-03-09
Posts: 913
Website

Re: Factoring x^3-3x^2+x=0

That’s all you can do. The quadratic polynomial

is irreducible over
and
.

In a way you could write

but this is probably not what you want.