Solve for x
x\in \left(-2,-\frac{5}{3}\right)
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3x^{2}+11x+10<0
Multiply the inequality by -1 to make the coefficient of the highest power in -3x^{2}-11x-10 positive. Since -1 is negative, the inequality direction is changed.
3x^{2}+11x+10=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{-11±\sqrt{11^{2}-4\times 3\times 10}}{2\times 3}
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 3 for a, 11 for b, and 10 for c in the quadratic formula.
x=\frac{-11±1}{6}
Do the calculations.
x=-\frac{5}{3} x=-2
Solve the equation x=\frac{-11±1}{6} when ± is plus and when ± is minus.
3\left(x+\frac{5}{3}\right)\left(x+2\right)<0
Rewrite the inequality by using the obtained solutions.
x+\frac{5}{3}>0 x+2<0
For the product to be negative, x+\frac{5}{3} and x+2 have to be of the opposite signs. Consider the case when x+\frac{5}{3} is positive and x+2 is negative.
x\in \emptyset
This is false for any x.
x+2>0 x+\frac{5}{3}<0
Consider the case when x+2 is positive and x+\frac{5}{3} is negative.
x\in \left(-2,-\frac{5}{3}\right)
The solution satisfying both inequalities is x\in \left(-2,-\frac{5}{3}\right).
x\in \left(-2,-\frac{5}{3}\right)
The final solution is the union of the obtained solutions.
Examples
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Linear equation
y = 3x + 4
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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}