0

I would be happy to get some ideas on possible approaches to solve $$ x^3 - x^2 < 2x - 2\qquad (x \in \mathbb R). $$

  • 2
    Factorise it: $x^2(x-1)<2(x-1)$ i.e. $(x^2-2)(x-1)<0$ i.e. $(x-\sqrt{2})(x+\sqrt{2})(x-1)<0$. When is the product of three numbers negative? –  Sep 15 '21 at 10:55
  • 1
    Factorise $x^3-x^2-2x+2$ and use wavy curve method. – Z Ahmed Sep 15 '21 at 10:56

1 Answers1

2

$$x^3-x^2-2x-2<0$$

$$(x-1)(x^2-2)<0$$

$$x\in (-\infty, -\sqrt2)\cup(1,\sqrt2)$$

enter image description here