Solve for x
x=2\sqrt{2}-2\approx 0.828427125
x=-2\sqrt{2}-2\approx -4.828427125
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\left(x-2\right)^{2}=x^{2}\times 2
Variable x cannot be equal to any of the values 0,2 since division by zero is not defined. Multiply both sides of the equation by x^{2}\left(x-2\right)^{2}, the least common multiple of x^{2},\left(2-x\right)^{2}.
x^{2}-4x+4=x^{2}\times 2
Use binomial theorem \left(a-b\right)^{2}=a^{2}-2ab+b^{2} to expand \left(x-2\right)^{2}.
x^{2}-4x+4-x^{2}\times 2=0
Subtract x^{2}\times 2 from both sides.
-x^{2}-4x+4=0
Combine x^{2} and -x^{2}\times 2 to get -x^{2}.
x=\frac{-\left(-4\right)±\sqrt{\left(-4\right)^{2}-4\left(-1\right)\times 4}}{2\left(-1\right)}
This equation is in standard form: ax^{2}+bx+c=0. Substitute -1 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(-1\right)\times 4}}{2\left(-1\right)}
Square -4.
x=\frac{-\left(-4\right)±\sqrt{16+4\times 4}}{2\left(-1\right)}
Multiply -4 times -1.
x=\frac{-\left(-4\right)±\sqrt{16+16}}{2\left(-1\right)}
Multiply 4 times 4.
x=\frac{-\left(-4\right)±\sqrt{32}}{2\left(-1\right)}
Add 16 to 16.
x=\frac{-\left(-4\right)±4\sqrt{2}}{2\left(-1\right)}
Take the square root of 32.
x=\frac{4±4\sqrt{2}}{2\left(-1\right)}
The opposite of -4 is 4.
x=\frac{4±4\sqrt{2}}{-2}
Multiply 2 times -1.
x=\frac{4\sqrt{2}+4}{-2}
Now solve the equation x=\frac{4±4\sqrt{2}}{-2} when ± is plus. Add 4 to 4\sqrt{2}.
x=-2\sqrt{2}-2
Divide 4+4\sqrt{2} by -2.
x=\frac{4-4\sqrt{2}}{-2}
Now solve the equation x=\frac{4±4\sqrt{2}}{-2} when ± is minus. Subtract 4\sqrt{2} from 4.
x=2\sqrt{2}-2
Divide 4-4\sqrt{2} by -2.
x=-2\sqrt{2}-2 x=2\sqrt{2}-2
The equation is now solved.
\left(x-2\right)^{2}=x^{2}\times 2
Variable x cannot be equal to any of the values 0,2 since division by zero is not defined. Multiply both sides of the equation by x^{2}\left(x-2\right)^{2}, the least common multiple of x^{2},\left(2-x\right)^{2}.
x^{2}-4x+4=x^{2}\times 2
Use binomial theorem \left(a-b\right)^{2}=a^{2}-2ab+b^{2} to expand \left(x-2\right)^{2}.
x^{2}-4x+4-x^{2}\times 2=0
Subtract x^{2}\times 2 from both sides.
-x^{2}-4x+4=0
Combine x^{2} and -x^{2}\times 2 to get -x^{2}.
-x^{2}-4x=-4
Subtract 4 from both sides. Anything subtracted from zero gives its negation.
\frac{-x^{2}-4x}{-1}=-\frac{4}{-1}
Divide both sides by -1.
x^{2}+\left(-\frac{4}{-1}\right)x=-\frac{4}{-1}
Dividing by -1 undoes the multiplication by -1.
x^{2}+4x=-\frac{4}{-1}
Divide -4 by -1.
x^{2}+4x=4
Divide -4 by -1.
x^{2}+4x+2^{2}=4+2^{2}
Divide 4, the coefficient of the x term, by 2 to get 2. Then add the square of 2 to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}+4x+4=4+4
Square 2.
x^{2}+4x+4=8
Add 4 to 4.
\left(x+2\right)^{2}=8
Factor x^{2}+4x+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+2\right)^{2}}=\sqrt{8}
Take the square root of both sides of the equation.
x+2=2\sqrt{2} x+2=-2\sqrt{2}
Simplify.
x=2\sqrt{2}-2 x=-2\sqrt{2}-2
Subtract 2 from 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}