Given the inequality:
$$\frac{\left(2 - x^{2}\right) \left(x - 3\right)^{3}}{\left(x + 1\right) \left(x^{2} - 3 x - 4\right)} \geq 0$$
To solve this inequality, we must first solve the corresponding equation:
$$\frac{\left(2 - x^{2}\right) \left(x - 3\right)^{3}}{\left(x + 1\right) \left(x^{2} - 3 x - 4\right)} = 0$$
Solve:
$$x_{1} = 3$$
$$x_{2} = - \sqrt{2}$$
$$x_{3} = \sqrt{2}$$
$$x_{1} = 3$$
$$x_{2} = - \sqrt{2}$$
$$x_{3} = \sqrt{2}$$
This roots
$$x_{2} = - \sqrt{2}$$
$$x_{3} = \sqrt{2}$$
$$x_{1} = 3$$
is the points with change the sign of the inequality expression.
First define with the sign to the leftmost point:
$$x_{0} \leq x_{2}$$
For example, let's take the point
$$x_{0} = x_{2} - \frac{1}{10}$$
=
$$- \sqrt{2} - \frac{1}{10}$$
=
$$- \sqrt{2} - \frac{1}{10}$$
substitute to the expression
$$\frac{\left(2 - x^{2}\right) \left(x - 3\right)^{3}}{\left(x + 1\right) \left(x^{2} - 3 x - 4\right)} \geq 0$$
$$\frac{\left(2 - \left(- \sqrt{2} - \frac{1}{10}\right)^{2}\right) \left(\left(-1\right) 3 - \left(\frac{1}{10} + \sqrt{2}\right)\right)^{3}}{\left(\left(- \sqrt{2} - \frac{1}{10}\right) + 1\right) \left(\left(-1\right) 4 + \left(- \sqrt{2} - \frac{1}{10}\right)^{2} - 3 \left(- \sqrt{2} - \frac{1}{10}\right)\right)} \geq 0$$
3 / 2\
/ 31 ___\ | / 1 ___\ |
|- -- - \/ 2 | *|2 - |- -- - \/ 2 | |
\ 10 / \ \ 10 / /
----------------------------------------------- >= 0
/ 2 \
/9 ___\ | 37 / 1 ___\ ___|
|-- - \/ 2 |*|- -- + |- -- - \/ 2 | + 3*\/ 2 |
\10 / \ 10 \ 10 / /
but
3 / 2\
/ 31 ___\ | / 1 ___\ |
|- -- - \/ 2 | *|2 - |- -- - \/ 2 | |
\ 10 / \ \ 10 / /
----------------------------------------------- < 0
/ 2 \
/9 ___\ | 37 / 1 ___\ ___|
|-- - \/ 2 |*|- -- + |- -- - \/ 2 | + 3*\/ 2 |
\10 / \ 10 \ 10 / /
Then
$$x \leq - \sqrt{2}$$
no execute
one of the solutions of our inequality is:
$$x \geq - \sqrt{2} \wedge x \leq \sqrt{2}$$
_____ _____
/ \ /
-------•-------•-------•-------
x_2 x_3 x_1
Other solutions will get with the changeover to the next point
etc.
The answer:
$$x \geq - \sqrt{2} \wedge x \leq \sqrt{2}$$
$$x \geq 3$$