Skip to main content
Solve for x (complex solution)
Tick mark Image
Graph

Similar Problems from Web Search

Share

3x^{2}-x+2-2x=-6
Subtract 2x from both sides.
3x^{2}-3x+2=-6
Combine -x and -2x to get -3x.
3x^{2}-3x+2+6=0
Add 6 to both sides.
3x^{2}-3x+8=0
Add 2 and 6 to get 8.
x=\frac{-\left(-3\right)±\sqrt{\left(-3\right)^{2}-4\times 3\times 8}}{2\times 3}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 3 for a, -3 for b, and 8 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-\left(-3\right)±\sqrt{9-4\times 3\times 8}}{2\times 3}
Square -3.
x=\frac{-\left(-3\right)±\sqrt{9-12\times 8}}{2\times 3}
Multiply -4 times 3.
x=\frac{-\left(-3\right)±\sqrt{9-96}}{2\times 3}
Multiply -12 times 8.
x=\frac{-\left(-3\right)±\sqrt{-87}}{2\times 3}
Add 9 to -96.
x=\frac{-\left(-3\right)±\sqrt{87}i}{2\times 3}
Take the square root of -87.
x=\frac{3±\sqrt{87}i}{2\times 3}
The opposite of -3 is 3.
x=\frac{3±\sqrt{87}i}{6}
Multiply 2 times 3.
x=\frac{3+\sqrt{87}i}{6}
Now solve the equation x=\frac{3±\sqrt{87}i}{6} when ± is plus. Add 3 to i\sqrt{87}.
x=\frac{\sqrt{87}i}{6}+\frac{1}{2}
Divide 3+i\sqrt{87} by 6.
x=\frac{-\sqrt{87}i+3}{6}
Now solve the equation x=\frac{3±\sqrt{87}i}{6} when ± is minus. Subtract i\sqrt{87} from 3.
x=-\frac{\sqrt{87}i}{6}+\frac{1}{2}
Divide 3-i\sqrt{87} by 6.
x=\frac{\sqrt{87}i}{6}+\frac{1}{2} x=-\frac{\sqrt{87}i}{6}+\frac{1}{2}
The equation is now solved.
3x^{2}-x+2-2x=-6
Subtract 2x from both sides.
3x^{2}-3x+2=-6
Combine -x and -2x to get -3x.
3x^{2}-3x=-6-2
Subtract 2 from both sides.
3x^{2}-3x=-8
Subtract 2 from -6 to get -8.
\frac{3x^{2}-3x}{3}=-\frac{8}{3}
Divide both sides by 3.
x^{2}+\left(-\frac{3}{3}\right)x=-\frac{8}{3}
Dividing by 3 undoes the multiplication by 3.
x^{2}-x=-\frac{8}{3}
Divide -3 by 3.
x^{2}-x+\left(-\frac{1}{2}\right)^{2}=-\frac{8}{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{8}{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{29}{12}
Add -\frac{8}{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{29}{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{29}{12}}
Take the square root of both sides of the equation.
x-\frac{1}{2}=\frac{\sqrt{87}i}{6} x-\frac{1}{2}=-\frac{\sqrt{87}i}{6}
Simplify.
x=\frac{\sqrt{87}i}{6}+\frac{1}{2} x=-\frac{\sqrt{87}i}{6}+\frac{1}{2}
Add \frac{1}{2} to both sides of the equation.