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(x-2)^3*(x+1)(x-1)^2*(x^2+2x+5)<0 inequation

A inequation with variable

The solution

You have entered [src]
       3                2 / 2          \    
(x - 2) *(x + 1)*(x - 1) *\x  + 2*x + 5/ < 0
$$\left(x - 2\right)^{3} \left(x + 1\right) \left(x - 1\right)^{2} \left(\left(x^{2} + 2 x\right) + 5\right) < 0$$
(((x - 2)^3*(x + 1))*(x - 1)^2)*(x^2 + 2*x + 5) < 0
Detail solution
Given the inequality:
$$\left(x - 2\right)^{3} \left(x + 1\right) \left(x - 1\right)^{2} \left(\left(x^{2} + 2 x\right) + 5\right) < 0$$
To solve this inequality, we must first solve the corresponding equation:
$$\left(x - 2\right)^{3} \left(x + 1\right) \left(x - 1\right)^{2} \left(\left(x^{2} + 2 x\right) + 5\right) = 0$$
Solve:
$$x_{1} = -1$$
$$x_{2} = 1$$
$$x_{3} = 2$$
$$x_{4} = -1 - 2 i$$
$$x_{5} = -1 + 2 i$$
Exclude the complex solutions:
$$x_{1} = -1$$
$$x_{2} = 1$$
$$x_{3} = 2$$
This roots
$$x_{1} = -1$$
$$x_{2} = 1$$
$$x_{3} = 2$$
is the points with change the sign of the inequality expression.
First define with the sign to the leftmost point:
$$x_{0} < x_{1}$$
For example, let's take the point
$$x_{0} = x_{1} - \frac{1}{10}$$
=
$$-1 + - \frac{1}{10}$$
=
$$- \frac{11}{10}$$
substitute to the expression
$$\left(x - 2\right)^{3} \left(x + 1\right) \left(x - 1\right)^{2} \left(\left(x^{2} + 2 x\right) + 5\right) < 0$$
$$\left(-2 - \frac{11}{10}\right)^{3} \left(- \frac{11}{10} + 1\right) \left(- \frac{11}{10} - 1\right)^{2} \left(\left(\frac{\left(-11\right) 2}{10} + \left(- \frac{11}{10}\right)^{2}\right) + 5\right) < 0$$
5268270231    
---------- < 0
100000000     

but
5268270231    
---------- > 0
100000000     

Then
$$x < -1$$
no execute
one of the solutions of our inequality is:
$$x > -1 \wedge x < 1$$
         _____           _____  
        /     \         /
-------ο-------ο-------ο-------
       x1      x2      x3

Other solutions will get with the changeover to the next point
etc.
The answer:
$$x > -1 \wedge x < 1$$
$$x > 2$$
Rapid solution [src]
Or(And(-1 < x, x < 1), And(1 < x, x < 2))
$$\left(-1 < x \wedge x < 1\right) \vee \left(1 < x \wedge x < 2\right)$$
((-1 < x)∧(x < 1))∨((1 < x)∧(x < 2))
Rapid solution 2 [src]
(-1, 1) U (1, 2)
$$x\ in\ \left(-1, 1\right) \cup \left(1, 2\right)$$
x in Union(Interval.open(-1, 1), Interval.open(1, 2))