Don't know how to solve inequality $x^4-2x^3+x^2 < 4$ Solve the inequality: $x^4-2x^3+x^2 &lt; 4$

I'm simply not sure about how to go about solving this inequality - it looks rather different from what I'm used to. Any help would be greatly appreciated.
$$x^4-2x^3+x^2-4 &lt; 0$$

$$(x-2)(x^3+x+2)&lt;0$$

$$(x-2)(x+1)(x^2-x+2)&lt;0$$

Notice that $x^2-x+2 &gt; 0$, are you able to take it form here?
A strategy you can use in this case is:


Make $y=x^2$
Solve the inequality for $y$
Go back to the $x$ variable for each inequality you found as solution for $y$