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3x^2>=3 inequation

A inequation with variable

The solution

You have entered [src]
   2     
3*x  >= 3
3x233 x^{2} \geq 3
3*x^2 >= 3
Detail solution
Given the inequality:
3x233 x^{2} \geq 3
To solve this inequality, we must first solve the corresponding equation:
3x2=33 x^{2} = 3
Solve:
Move right part of the equation to
left part with negative sign.

The equation is transformed from
3x2=33 x^{2} = 3
to
3x23=03 x^{2} - 3 = 0
This equation is of the form
a*x^2 + b*x + c = 0

A quadratic equation can be solved
using the discriminant.
The roots of the quadratic equation:
x1=Db2ax_{1} = \frac{\sqrt{D} - b}{2 a}
x2=Db2ax_{2} = \frac{- \sqrt{D} - b}{2 a}
where D = b^2 - 4*a*c - it is the discriminant.
Because
a=3a = 3
b=0b = 0
c=3c = -3
, then
D = b^2 - 4 * a * c = 

(0)^2 - 4 * (3) * (-3) = 36

Because D > 0, then the equation has two roots.
x1 = (-b + sqrt(D)) / (2*a)

x2 = (-b - sqrt(D)) / (2*a)

or
x1=1x_{1} = 1
x2=1x_{2} = -1
x1=1x_{1} = 1
x2=1x_{2} = -1
x1=1x_{1} = 1
x2=1x_{2} = -1
This roots
x2=1x_{2} = -1
x1=1x_{1} = 1
is the points with change the sign of the inequality expression.
First define with the sign to the leftmost point:
x0x2x_{0} \leq x_{2}
For example, let's take the point
x0=x2110x_{0} = x_{2} - \frac{1}{10}
=
1+110-1 + - \frac{1}{10}
=
1110- \frac{11}{10}
substitute to the expression
3x233 x^{2} \geq 3
3(1110)233 \left(- \frac{11}{10}\right)^{2} \geq 3
363     
--- >= 3
100     

one of the solutions of our inequality is:
x1x \leq -1
 _____           _____          
      \         /
-------•-------•-------
       x2      x1

Other solutions will get with the changeover to the next point
etc.
The answer:
x1x \leq -1
x1x \geq 1
Solving inequality on a graph
-5.0-4.0-3.0-2.0-1.05.00.01.02.03.04.00100
Rapid solution [src]
Or(And(1 <= x, x < oo), And(x <= -1, -oo < x))
(1xx<)(x1<x)\left(1 \leq x \wedge x < \infty\right) \vee \left(x \leq -1 \wedge -\infty < x\right)
((1 <= x)∧(x < oo))∨((x <= -1)∧(-oo < x))
Rapid solution 2 [src]
(-oo, -1] U [1, oo)
x in (,1][1,)x\ in\ \left(-\infty, -1\right] \cup \left[1, \infty\right)
x in Union(Interval(-oo, -1), Interval(1, oo))