Solve for x (complex solution)
x=\frac{\sqrt{2}i}{2}+1\approx 1+0.707106781i
x=-\frac{\sqrt{2}i}{2}+1\approx 1-0.707106781i
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x^{2}-2x+\frac{3}{2}=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(-2\right)±\sqrt{\left(-2\right)^{2}-4\times \frac{3}{2}}}{2}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 1 for a, -2 for b, and \frac{3}{2} for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-\left(-2\right)±\sqrt{4-4\times \frac{3}{2}}}{2}
Square -2.
x=\frac{-\left(-2\right)±\sqrt{4-6}}{2}
Multiply -4 times \frac{3}{2}.
x=\frac{-\left(-2\right)±\sqrt{-2}}{2}
Add 4 to -6.
x=\frac{-\left(-2\right)±\sqrt{2}i}{2}
Take the square root of -2.
x=\frac{2±\sqrt{2}i}{2}
The opposite of -2 is 2.
x=\frac{2+\sqrt{2}i}{2}
Now solve the equation x=\frac{2±\sqrt{2}i}{2} when ± is plus. Add 2 to i\sqrt{2}.
x=\frac{\sqrt{2}i}{2}+1
Divide 2+i\sqrt{2} by 2.
x=\frac{-\sqrt{2}i+2}{2}
Now solve the equation x=\frac{2±\sqrt{2}i}{2} when ± is minus. Subtract i\sqrt{2} from 2.
x=-\frac{\sqrt{2}i}{2}+1
Divide 2-i\sqrt{2} by 2.
x=\frac{\sqrt{2}i}{2}+1 x=-\frac{\sqrt{2}i}{2}+1
The equation is now solved.
x^{2}-2x+\frac{3}{2}=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.
x^{2}-2x+\frac{3}{2}-\frac{3}{2}=-\frac{3}{2}
Subtract \frac{3}{2} from both sides of the equation.
x^{2}-2x=-\frac{3}{2}
Subtracting \frac{3}{2} from itself leaves 0.
x^{2}-2x+1=-\frac{3}{2}+1
Divide -2, the coefficient of the x term, by 2 to get -1. Then add the square of -1 to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}-2x+1=-\frac{1}{2}
Add -\frac{3}{2} to 1.
\left(x-1\right)^{2}=-\frac{1}{2}
Factor x^{2}-2x+1. 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-1\right)^{2}}=\sqrt{-\frac{1}{2}}
Take the square root of both sides of the equation.
x-1=\frac{\sqrt{2}i}{2} x-1=-\frac{\sqrt{2}i}{2}
Simplify.
x=\frac{\sqrt{2}i}{2}+1 x=-\frac{\sqrt{2}i}{2}+1
Add 1 to both sides of the equation.
Examples
Quadratic equation
{ 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}