Nonstandard inequality with parameter and absolute value

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The given inequality is $|x^2-ax+1|<3(x^2+x+1)$. The question is:

For which values of $a$, every $x$ is a solution?

I am trying to solve it by making the graphics of the two sides of the inequality but have hard time doing so.

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Hint: Consider the cases $$x^2-ax+1\geq 0$$ and $$x^2-ax+1<0$$ In the first case you have to consider the inequality: $$x^2-ax+1<3(x^2+x+1)$$ and so on.