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-\frac{3}{2}x^{2}-4x-3=1
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.
-\frac{3}{2}x^{2}-4x-3-1=1-1
Subtract 1 from both sides of the equation.
-\frac{3}{2}x^{2}-4x-3-1=0
Subtracting 1 from itself leaves 0.
-\frac{3}{2}x^{2}-4x-4=0
Subtract 1 from -3.
x=\frac{-\left(-4\right)±\sqrt{\left(-4\right)^{2}-4\left(-\frac{3}{2}\right)\left(-4\right)}}{2\left(-\frac{3}{2}\right)}
This equation is in standard form: ax^{2}+bx+c=0. Substitute -\frac{3}{2} for a, -4 for b, and -4 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-\left(-4\right)±\sqrt{16-4\left(-\frac{3}{2}\right)\left(-4\right)}}{2\left(-\frac{3}{2}\right)}
Square -4.
x=\frac{-\left(-4\right)±\sqrt{16+6\left(-4\right)}}{2\left(-\frac{3}{2}\right)}
Multiply -4 times -\frac{3}{2}.
x=\frac{-\left(-4\right)±\sqrt{16-24}}{2\left(-\frac{3}{2}\right)}
Multiply 6 times -4.
x=\frac{-\left(-4\right)±\sqrt{-8}}{2\left(-\frac{3}{2}\right)}
Add 16 to -24.
x=\frac{-\left(-4\right)±2\sqrt{2}i}{2\left(-\frac{3}{2}\right)}
Take the square root of -8.
x=\frac{4±2\sqrt{2}i}{2\left(-\frac{3}{2}\right)}
The opposite of -4 is 4.
x=\frac{4±2\sqrt{2}i}{-3}
Multiply 2 times -\frac{3}{2}.
x=\frac{4+2\sqrt{2}i}{-3}
Now solve the equation x=\frac{4±2\sqrt{2}i}{-3} when ± is plus. Add 4 to 2i\sqrt{2}.
x=\frac{-2\sqrt{2}i-4}{3}
Divide 4+2i\sqrt{2} by -3.
x=\frac{-2\sqrt{2}i+4}{-3}
Now solve the equation x=\frac{4±2\sqrt{2}i}{-3} when ± is minus. Subtract 2i\sqrt{2} from 4.
x=\frac{-4+2\sqrt{2}i}{3}
Divide 4-2i\sqrt{2} by -3.
x=\frac{-2\sqrt{2}i-4}{3} x=\frac{-4+2\sqrt{2}i}{3}
The equation is now solved.
-\frac{3}{2}x^{2}-4x-3=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{3}{2}x^{2}-4x-3-\left(-3\right)=1-\left(-3\right)
Add 3 to both sides of the equation.
-\frac{3}{2}x^{2}-4x=1-\left(-3\right)
Subtracting -3 from itself leaves 0.
-\frac{3}{2}x^{2}-4x=4
Subtract -3 from 1.
\frac{-\frac{3}{2}x^{2}-4x}{-\frac{3}{2}}=\frac{4}{-\frac{3}{2}}
Divide both sides of the equation by -\frac{3}{2}, which is the same as multiplying both sides by the reciprocal of the fraction.
x^{2}+\left(-\frac{4}{-\frac{3}{2}}\right)x=\frac{4}{-\frac{3}{2}}
Dividing by -\frac{3}{2} undoes the multiplication by -\frac{3}{2}.
x^{2}+\frac{8}{3}x=\frac{4}{-\frac{3}{2}}
Divide -4 by -\frac{3}{2} by multiplying -4 by the reciprocal of -\frac{3}{2}.
x^{2}+\frac{8}{3}x=-\frac{8}{3}
Divide 4 by -\frac{3}{2} by multiplying 4 by the reciprocal of -\frac{3}{2}.
x^{2}+\frac{8}{3}x+\left(\frac{4}{3}\right)^{2}=-\frac{8}{3}+\left(\frac{4}{3}\right)^{2}
Divide \frac{8}{3}, the coefficient of the x term, by 2 to get \frac{4}{3}. Then add the square of \frac{4}{3} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}+\frac{8}{3}x+\frac{16}{9}=-\frac{8}{3}+\frac{16}{9}
Square \frac{4}{3} by squaring both the numerator and the denominator of the fraction.
x^{2}+\frac{8}{3}x+\frac{16}{9}=-\frac{8}{9}
Add -\frac{8}{3} to \frac{16}{9} by finding a common denominator and adding the numerators. Then reduce the fraction to lowest terms if possible.
\left(x+\frac{4}{3}\right)^{2}=-\frac{8}{9}
Factor x^{2}+\frac{8}{3}x+\frac{16}{9}. 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{4}{3}\right)^{2}}=\sqrt{-\frac{8}{9}}
Take the square root of both sides of the equation.
x+\frac{4}{3}=\frac{2\sqrt{2}i}{3} x+\frac{4}{3}=-\frac{2\sqrt{2}i}{3}
Simplify.
x=\frac{-4+2\sqrt{2}i}{3} x=\frac{-2\sqrt{2}i-4}{3}
Subtract \frac{4}{3} from both sides of the equation.