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4k^{2}-12k+9-4\left(3-2k\right)<0
Use binomial theorem \left(a-b\right)^{2}=a^{2}-2ab+b^{2} to expand \left(2k-3\right)^{2}.
4k^{2}-12k+9-12+8k<0
Use the distributive property to multiply -4 by 3-2k.
4k^{2}-12k-3+8k<0
Subtract 12 from 9 to get -3.
4k^{2}-4k-3<0
Combine -12k and 8k to get -4k.
4k^{2}-4k-3=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.
k=\frac{-\left(-4\right)±\sqrt{\left(-4\right)^{2}-4\times 4\left(-3\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, -4 for b, and -3 for c in the quadratic formula.
k=\frac{4±8}{8}
Do the calculations.
k=\frac{3}{2} k=-\frac{1}{2}
Solve the equation k=\frac{4±8}{8} when ± is plus and when ± is minus.
4\left(k-\frac{3}{2}\right)\left(k+\frac{1}{2}\right)<0
Rewrite the inequality by using the obtained solutions.
k-\frac{3}{2}>0 k+\frac{1}{2}<0
For the product to be negative, k-\frac{3}{2} and k+\frac{1}{2} have to be of the opposite signs. Consider the case when k-\frac{3}{2} is positive and k+\frac{1}{2} is negative.
k\in \emptyset
This is false for any k.
k+\frac{1}{2}>0 k-\frac{3}{2}<0
Consider the case when k+\frac{1}{2} is positive and k-\frac{3}{2} is negative.
k\in \left(-\frac{1}{2},\frac{3}{2}\right)
The solution satisfying both inequalities is k\in \left(-\frac{1}{2},\frac{3}{2}\right).
k\in \left(-\frac{1}{2},\frac{3}{2}\right)
The final solution is the union of the obtained solutions.