Solve for x
x\in (-\infty,-\frac{1}{2}]\cup [2,\infty)
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3\left(x-2\right)-2\left(x^{2}-4\right)\leq 0
Multiply both sides of the equation by 6, the least common multiple of 2,3. Since 6 is positive, the inequality direction remains the same.
3x-6-2\left(x^{2}-4\right)\leq 0
Use the distributive property to multiply 3 by x-2.
3x-6-2x^{2}+8\leq 0
Use the distributive property to multiply -2 by x^{2}-4.
3x+2-2x^{2}\leq 0
Add -6 and 8 to get 2.
-3x-2+2x^{2}\geq 0
Multiply the inequality by -1 to make the coefficient of the highest power in 3x+2-2x^{2} positive. Since -1 is negative, the inequality direction is changed.
-3x-2+2x^{2}=0
To solve the inequality, factor the left hand side. Quadratic polynomial can be factored using the transformation ax^{2}+bx+c=a\left(x-x_{1}\right)\left(x-x_{2}\right), where x_{1} and x_{2} are the solutions of the quadratic equation ax^{2}+bx+c=0.
x=\frac{-\left(-3\right)±\sqrt{\left(-3\right)^{2}-4\times 2\left(-2\right)}}{2\times 2}
All equations of the form ax^{2}+bx+c=0 can be solved using the quadratic formula: \frac{-b±\sqrt{b^{2}-4ac}}{2a}. Substitute 2 for a, -3 for b, and -2 for c in the quadratic formula.
x=\frac{3±5}{4}
Do the calculations.
x=2 x=-\frac{1}{2}
Solve the equation x=\frac{3±5}{4} when ± is plus and when ± is minus.
2\left(x-2\right)\left(x+\frac{1}{2}\right)\geq 0
Rewrite the inequality by using the obtained solutions.
x-2\leq 0 x+\frac{1}{2}\leq 0
For the product to be ≥0, x-2 and x+\frac{1}{2} have to be both ≤0 or both ≥0. Consider the case when x-2 and x+\frac{1}{2} are both ≤0.
x\leq -\frac{1}{2}
The solution satisfying both inequalities is x\leq -\frac{1}{2}.
x+\frac{1}{2}\geq 0 x-2\geq 0
Consider the case when x-2 and x+\frac{1}{2} are both ≥0.
x\geq 2
The solution satisfying both inequalities is x\geq 2.
x\leq -\frac{1}{2}\text{; }x\geq 2
The final solution is the union of the obtained solutions.
Examples
Quadratic equation
{ x } ^ { 2 } - 4 x - 5 = 0
Trigonometry
4 \sin \theta \cos \theta = 2 \sin \theta
Linear equation
y = 3x + 4
Arithmetic
699 * 533
Matrix
\left[ \begin{array} { l l } { 2 } & { 3 } \\ { 5 } & { 4 } \end{array} \right] \left[ \begin{array} { l l l } { 2 } & { 0 } & { 3 } \\ { -1 } & { 1 } & { 5 } \end{array} \right]
Simultaneous equation
\left. \begin{cases} { 8x+2y = 46 } \\ { 7x+3y = 47 } \end{cases} \right.
Differentiation
\frac { d } { d x } \frac { ( 3 x ^ { 2 } - 2 ) } { ( x - 5 ) }
Integration
\int _ { 0 } ^ { 1 } x e ^ { - x ^ { 2 } } d x
Limits
\lim _{x \rightarrow-3} \frac{x^{2}-9}{x^{2}+2 x-3}