When (x^9 - x) is factored as completely as possible into polynomials and monomials with integral coefficients, how many factors are there?
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Notice that
[tex](x^9-x)=x(x^8-1)[/tex]Furthermore,
[tex](x^8-1)=(x^4+1)(x^4-1)=(x^4+1)(x^2+1)(x^2-1)=(x^4+1)(x^2+1)(x+1)(x-1)[/tex]Then,
[tex](x^9-x)=x(x^4+1)(x^2+1)(x+1)(x-1)[/tex]This expression cannot be further simplified. There are 5 factors in total, one monomial and four binomials.