Factoring a Polynomial with Non-Integer Roots

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f(t) = t^3 - 6t^2 +9t + 2

f(1) is not equal to 0
f(-1) is not equal to 0
f(2) is not equal to 0
f(-2) is not equal to 0
No common factor, can't group either

How can I work this one out?
thx
 
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Here's something to remember.
If f=a_0+a_1x+...+a_n x^n is a polynomial with integer coefficients of degree >=1 and q=b/c (ggd(b,c)=1) is a rational root, then b|a_0 and c|a_n.
So the possible rational roots of your polynomial are \pm 2, which not roots. This means there are no rational roots so it's a nasty polynomial.
 
I don't believe this is factorable
 
Of course it's factorable, over some field, it's just that the roots aren't integers (or rational). There's even a formula for the roots. try googling for it.
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
Prove $$\int\limits_0^{\sqrt2/4}\frac{1}{\sqrt{x-x^2}}\arcsin\sqrt{\frac{(x-1)\left(x-1+x\sqrt{9-16x}\right)}{1-2x}} \, \mathrm dx = \frac{\pi^2}{8}.$$ Let $$I = \int\limits_0^{\sqrt 2 / 4}\frac{1}{\sqrt{x-x^2}}\arcsin\sqrt{\frac{(x-1)\left(x-1+x\sqrt{9-16x}\right)}{1-2x}} \, \mathrm dx. \tag{1}$$ The representation integral of ##\arcsin## is $$\arcsin u = \int\limits_{0}^{1} \frac{\mathrm dt}{\sqrt{1-t^2}}, \qquad 0 \leqslant u \leqslant 1.$$ Plugging identity above into ##(1)## with ##u...
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