inequality with parameter - designate param that we get R for which param of A set of solutions is R?
$$-3 < {x^2 - ax - 2\over x^2 - x +1}  < 2$$
hm
my trying:
$x^2-x+1$ is always +  so I can multiply by $x^2-x+1$ instead of $(x^2-x+1)^2$
result should be set of $(-1 ;2 $ )

We need
$$x^2-ax-2<2x^2-2x+2$$ or
$$x^2+(a-2)x+4>0,$$ for which we need
$$(a-2)^2-4\cdot1\cdot4<0.$$
Also, we need $$x^2-ax-2+3x^2-3x+3>0$$ or
$$4x^2-(a+3)x+1>0,$$ for which we need $$(a+3)^2-4\cdot4\cdot1<0.$$
Now, solve this system.
I got $$-2<a<1.$$
