
factoring a quadrinomial
Hi,
I'm trying to factor $\displaystyle x^3+3x+2$ so I can find the zeros (well its actually part of a linear algebra prob. for which I need to find the eigenvalues) but I can't figure out how to factor it... even after consulting tutorial sites to dust off my factoring skills :S...
Help?

x^3+3x+2=x^3+x+2x+2=x(x^21)+2(x+1)=x(x1)(x+1)+2(x+1)=
(x+1)[x(x1)+2]=(x+1)(x^2+x+2)
x^2+x+2=0
D=1+8=9
x1=1
x2=2
x^2+x+2=(x+1)(x2)
(x+1)(x^2+x+2)=(x+1)(x+1)(x2)=(x+1)^2(x2)