Solve for x (complex solution)
x=-\frac{\sqrt{3}i}{6}+\frac{1}{2}\approx 0.5-0.288675135i
x=\frac{\sqrt{3}i}{6}+\frac{1}{2}\approx 0.5+0.288675135i
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x-3x^{2}=-2x+1
Subtract 3x^{2} from both sides.
x-3x^{2}+2x=1
Add 2x to both sides.
3x-3x^{2}=1
Combine x and 2x to get 3x.
3x-3x^{2}-1=0
Subtract 1 from both sides.
-3x^{2}+3x-1=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{-3±\sqrt{3^{2}-4\left(-3\right)\left(-1\right)}}{2\left(-3\right)}
This equation is in standard form: ax^{2}+bx+c=0. Substitute -3 for a, 3 for b, and -1 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-3±\sqrt{9-4\left(-3\right)\left(-1\right)}}{2\left(-3\right)}
Square 3.
x=\frac{-3±\sqrt{9+12\left(-1\right)}}{2\left(-3\right)}
Multiply -4 times -3.
x=\frac{-3±\sqrt{9-12}}{2\left(-3\right)}
Multiply 12 times -1.
x=\frac{-3±\sqrt{-3}}{2\left(-3\right)}
Add 9 to -12.
x=\frac{-3±\sqrt{3}i}{2\left(-3\right)}
Take the square root of -3.
x=\frac{-3±\sqrt{3}i}{-6}
Multiply 2 times -3.
x=\frac{-3+\sqrt{3}i}{-6}
Now solve the equation x=\frac{-3±\sqrt{3}i}{-6} when ± is plus. Add -3 to i\sqrt{3}.
x=-\frac{\sqrt{3}i}{6}+\frac{1}{2}
Divide -3+i\sqrt{3} by -6.
x=\frac{-\sqrt{3}i-3}{-6}
Now solve the equation x=\frac{-3±\sqrt{3}i}{-6} when ± is minus. Subtract i\sqrt{3} from -3.
x=\frac{\sqrt{3}i}{6}+\frac{1}{2}
Divide -3-i\sqrt{3} by -6.
x=-\frac{\sqrt{3}i}{6}+\frac{1}{2} x=\frac{\sqrt{3}i}{6}+\frac{1}{2}
The equation is now solved.
x-3x^{2}=-2x+1
Subtract 3x^{2} from both sides.
x-3x^{2}+2x=1
Add 2x to both sides.
3x-3x^{2}=1
Combine x and 2x to get 3x.
-3x^{2}+3x=1
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.
\frac{-3x^{2}+3x}{-3}=\frac{1}{-3}
Divide both sides by -3.
x^{2}+\frac{3}{-3}x=\frac{1}{-3}
Dividing by -3 undoes the multiplication by -3.
x^{2}-x=\frac{1}{-3}
Divide 3 by -3.
x^{2}-x=-\frac{1}{3}
Divide 1 by -3.
x^{2}-x+\left(-\frac{1}{2}\right)^{2}=-\frac{1}{3}+\left(-\frac{1}{2}\right)^{2}
Divide -1, the coefficient of the x term, by 2 to get -\frac{1}{2}. Then add the square of -\frac{1}{2} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}-x+\frac{1}{4}=-\frac{1}{3}+\frac{1}{4}
Square -\frac{1}{2} by squaring both the numerator and the denominator of the fraction.
x^{2}-x+\frac{1}{4}=-\frac{1}{12}
Add -\frac{1}{3} to \frac{1}{4} by finding a common denominator and adding the numerators. Then reduce the fraction to lowest terms if possible.
\left(x-\frac{1}{2}\right)^{2}=-\frac{1}{12}
Factor x^{2}-x+\frac{1}{4}. 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}{2}\right)^{2}}=\sqrt{-\frac{1}{12}}
Take the square root of both sides of the equation.
x-\frac{1}{2}=\frac{\sqrt{3}i}{6} x-\frac{1}{2}=-\frac{\sqrt{3}i}{6}
Simplify.
x=\frac{\sqrt{3}i}{6}+\frac{1}{2} x=-\frac{\sqrt{3}i}{6}+\frac{1}{2}
Add \frac{1}{2} to both sides of the equation.
Examples
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{ 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}