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2x^{2}-x+\frac{1}{8}=0
All equations of the form ax^{2}+bx+c=0 can be solved using the quadratic formula: \frac{-b±\sqrt{b^{2}-4ac}}{2a}. The quadratic formula gives two solutions, one when ± is addition and one when it is subtraction.
x=\frac{-\left(-1\right)±\sqrt{1-4\times 2\times \frac{1}{8}}}{2\times 2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 2 for a, -1 for b, and \frac{1}{8} for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-\left(-1\right)±\sqrt{1-8\times \frac{1}{8}}}{2\times 2}
Multiply -4 times 2.
x=\frac{-\left(-1\right)±\sqrt{1-1}}{2\times 2}
Multiply -8 times \frac{1}{8}.
x=\frac{-\left(-1\right)±\sqrt{0}}{2\times 2}
Add 1 to -1.
x=-\frac{-1}{2\times 2}
Take the square root of 0.
x=\frac{1}{2\times 2}
The opposite of -1 is 1.
x=\frac{1}{4}
Multiply 2 times 2.
2x^{2}-x+\frac{1}{8}=0
Quadratic equations such as this one can be solved by completing the square. In order to complete the square, the equation must first be in the form x^{2}+bx=c.
2x^{2}-x+\frac{1}{8}-\frac{1}{8}=-\frac{1}{8}
Subtract \frac{1}{8} from both sides of the equation.
2x^{2}-x=-\frac{1}{8}
Subtracting \frac{1}{8} from itself leaves 0.
\frac{2x^{2}-x}{2}=-\frac{\frac{1}{8}}{2}
Divide both sides by 2.
x^{2}-\frac{1}{2}x=-\frac{\frac{1}{8}}{2}
Dividing by 2 undoes the multiplication by 2.
x^{2}-\frac{1}{2}x=-\frac{1}{16}
Divide -\frac{1}{8} by 2.
x^{2}-\frac{1}{2}x+\left(-\frac{1}{4}\right)^{2}=-\frac{1}{16}+\left(-\frac{1}{4}\right)^{2}
Divide -\frac{1}{2}, the coefficient of the x term, by 2 to get -\frac{1}{4}. Then add the square of -\frac{1}{4} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}-\frac{1}{2}x+\frac{1}{16}=\frac{-1+1}{16}
Square -\frac{1}{4} by squaring both the numerator and the denominator of the fraction.
x^{2}-\frac{1}{2}x+\frac{1}{16}=0
Add -\frac{1}{16} to \frac{1}{16} by finding a common denominator and adding the numerators. Then reduce the fraction to lowest terms if possible.
\left(x-\frac{1}{4}\right)^{2}=0
Factor x^{2}-\frac{1}{2}x+\frac{1}{16}. In general, when x^{2}+bx+c is a perfect square, it can always be factored as \left(x+\frac{b}{2}\right)^{2}.
\sqrt{\left(x-\frac{1}{4}\right)^{2}}=\sqrt{0}
Take the square root of both sides of the equation.
x-\frac{1}{4}=0 x-\frac{1}{4}=0
Simplify.
x=\frac{1}{4} x=\frac{1}{4}
Add \frac{1}{4} to both sides of the equation.
x=\frac{1}{4}
The equation is now solved. Solutions are the same.