Solve for k
k\in \mathrm{R}
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16k^{2}-64k+64-4\left(1-k\right)\times 4>0
Use binomial theorem \left(a-b\right)^{2}=a^{2}-2ab+b^{2} to expand \left(4k-8\right)^{2}.
16k^{2}-64k+64-16\left(1-k\right)>0
Multiply 4 and 4 to get 16.
16k^{2}-64k+64-16+16k>0
Use the distributive property to multiply -16 by 1-k.
16k^{2}-64k+48+16k>0
Subtract 16 from 64 to get 48.
16k^{2}-48k+48>0
Combine -64k and 16k to get -48k.
16k^{2}-48k+48=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(-48\right)±\sqrt{\left(-48\right)^{2}-4\times 16\times 48}}{2\times 16}
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 16 for a, -48 for b, and 48 for c in the quadratic formula.
k=\frac{48±\sqrt{-768}}{32}
Do the calculations.
16\times 0^{2}-48\times 0+48=48
Since the square root of a negative number is not defined in the real field, there are no solutions. Expression 16k^{2}-48k+48 has the same sign for any k. To determine the sign, calculate the value of the expression for k=0.
k\in \mathrm{R}
The value of the expression 16k^{2}-48k+48 is always positive. Inequality holds for k\in \mathrm{R}.
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