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