Solve for m
m\in (-\infty,\frac{2}{5}]\cup [1,\infty)
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36m^{2}-4\left(m+2\right)\left(4m-1\right)\geq 0
Multiply -1 and 4 to get -4.
36m^{2}+\left(-4m-8\right)\left(4m-1\right)\geq 0
Use the distributive property to multiply -4 by m+2.
36m^{2}-16m^{2}-28m+8\geq 0
Use the distributive property to multiply -4m-8 by 4m-1 and combine like terms.
20m^{2}-28m+8\geq 0
Combine 36m^{2} and -16m^{2} to get 20m^{2}.
20m^{2}-28m+8=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.
m=\frac{-\left(-28\right)±\sqrt{\left(-28\right)^{2}-4\times 20\times 8}}{2\times 20}
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 20 for a, -28 for b, and 8 for c in the quadratic formula.
m=\frac{28±12}{40}
Do the calculations.
m=1 m=\frac{2}{5}
Solve the equation m=\frac{28±12}{40} when ± is plus and when ± is minus.
20\left(m-1\right)\left(m-\frac{2}{5}\right)\geq 0
Rewrite the inequality by using the obtained solutions.
m-1\leq 0 m-\frac{2}{5}\leq 0
For the product to be ≥0, m-1 and m-\frac{2}{5} have to be both ≤0 or both ≥0. Consider the case when m-1 and m-\frac{2}{5} are both ≤0.
m\leq \frac{2}{5}
The solution satisfying both inequalities is m\leq \frac{2}{5}.
m-\frac{2}{5}\geq 0 m-1\geq 0
Consider the case when m-1 and m-\frac{2}{5} are both ≥0.
m\geq 1
The solution satisfying both inequalities is m\geq 1.
m\leq \frac{2}{5}\text{; }m\geq 1
The final solution is the union of the obtained solutions.
Examples
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Linear equation
y = 3x + 4
Arithmetic
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Matrix
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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}