Solve for m
m\in \left(-1,\frac{11}{4}\right)
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4m^{2}-4m+1-3\left(m+4\right)<0
Use binomial theorem \left(a-b\right)^{2}=a^{2}-2ab+b^{2} to expand \left(2m-1\right)^{2}.
4m^{2}-4m+1-3m-12<0
Use the distributive property to multiply -3 by m+4.
4m^{2}-7m+1-12<0
Combine -4m and -3m to get -7m.
4m^{2}-7m-11<0
Subtract 12 from 1 to get -11.
4m^{2}-7m-11=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(-7\right)±\sqrt{\left(-7\right)^{2}-4\times 4\left(-11\right)}}{2\times 4}
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 4 for a, -7 for b, and -11 for c in the quadratic formula.
m=\frac{7±15}{8}
Do the calculations.
m=\frac{11}{4} m=-1
Solve the equation m=\frac{7±15}{8} when ± is plus and when ± is minus.
4\left(m-\frac{11}{4}\right)\left(m+1\right)<0
Rewrite the inequality by using the obtained solutions.
m-\frac{11}{4}>0 m+1<0
For the product to be negative, m-\frac{11}{4} and m+1 have to be of the opposite signs. Consider the case when m-\frac{11}{4} is positive and m+1 is negative.
m\in \emptyset
This is false for any m.
m+1>0 m-\frac{11}{4}<0
Consider the case when m+1 is positive and m-\frac{11}{4} is negative.
m\in \left(-1,\frac{11}{4}\right)
The solution satisfying both inequalities is m\in \left(-1,\frac{11}{4}\right).
m\in \left(-1,\frac{11}{4}\right)
The final solution is the union of the obtained solutions.
Examples
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{ x } ^ { 2 } - 4 x - 5 = 0
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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}