Solve for x (complex solution)
x=\frac{-\sqrt{7}i+1}{8}\approx 0.125-0.330718914i
x=\frac{1+\sqrt{7}i}{8}\approx 0.125+0.330718914i
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\left(2x-1\right)\times 2-\left(2x+1\right)\times 2x=\left(2x-1\right)\left(2x+1\right)
Variable x cannot be equal to any of the values -\frac{1}{2},\frac{1}{2} since division by zero is not defined. Multiply both sides of the equation by \left(2x-1\right)\left(2x+1\right), the least common multiple of 2x+1,2x-1.
4x-2-\left(2x+1\right)\times 2x=\left(2x-1\right)\left(2x+1\right)
Use the distributive property to multiply 2x-1 by 2.
4x-2-\left(4x+2\right)x=\left(2x-1\right)\left(2x+1\right)
Use the distributive property to multiply 2x+1 by 2.
4x-2-\left(4x^{2}+2x\right)=\left(2x-1\right)\left(2x+1\right)
Use the distributive property to multiply 4x+2 by x.
4x-2-4x^{2}-2x=\left(2x-1\right)\left(2x+1\right)
To find the opposite of 4x^{2}+2x, find the opposite of each term.
2x-2-4x^{2}=\left(2x-1\right)\left(2x+1\right)
Combine 4x and -2x to get 2x.
2x-2-4x^{2}=\left(2x\right)^{2}-1
Consider \left(2x-1\right)\left(2x+1\right). Multiplication can be transformed into difference of squares using the rule: \left(a-b\right)\left(a+b\right)=a^{2}-b^{2}. Square 1.
2x-2-4x^{2}=2^{2}x^{2}-1
Expand \left(2x\right)^{2}.
2x-2-4x^{2}=4x^{2}-1
Calculate 2 to the power of 2 and get 4.
2x-2-4x^{2}-4x^{2}=-1
Subtract 4x^{2} from both sides.
2x-2-8x^{2}=-1
Combine -4x^{2} and -4x^{2} to get -8x^{2}.
2x-2-8x^{2}+1=0
Add 1 to both sides.
2x-1-8x^{2}=0
Add -2 and 1 to get -1.
-8x^{2}+2x-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{-2±\sqrt{2^{2}-4\left(-8\right)\left(-1\right)}}{2\left(-8\right)}
This equation is in standard form: ax^{2}+bx+c=0. Substitute -8 for a, 2 for b, and -1 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-2±\sqrt{4-4\left(-8\right)\left(-1\right)}}{2\left(-8\right)}
Square 2.
x=\frac{-2±\sqrt{4+32\left(-1\right)}}{2\left(-8\right)}
Multiply -4 times -8.
x=\frac{-2±\sqrt{4-32}}{2\left(-8\right)}
Multiply 32 times -1.
x=\frac{-2±\sqrt{-28}}{2\left(-8\right)}
Add 4 to -32.
x=\frac{-2±2\sqrt{7}i}{2\left(-8\right)}
Take the square root of -28.
x=\frac{-2±2\sqrt{7}i}{-16}
Multiply 2 times -8.
x=\frac{-2+2\sqrt{7}i}{-16}
Now solve the equation x=\frac{-2±2\sqrt{7}i}{-16} when ± is plus. Add -2 to 2i\sqrt{7}.
x=\frac{-\sqrt{7}i+1}{8}
Divide -2+2i\sqrt{7} by -16.
x=\frac{-2\sqrt{7}i-2}{-16}
Now solve the equation x=\frac{-2±2\sqrt{7}i}{-16} when ± is minus. Subtract 2i\sqrt{7} from -2.
x=\frac{1+\sqrt{7}i}{8}
Divide -2-2i\sqrt{7} by -16.
x=\frac{-\sqrt{7}i+1}{8} x=\frac{1+\sqrt{7}i}{8}
The equation is now solved.
\left(2x-1\right)\times 2-\left(2x+1\right)\times 2x=\left(2x-1\right)\left(2x+1\right)
Variable x cannot be equal to any of the values -\frac{1}{2},\frac{1}{2} since division by zero is not defined. Multiply both sides of the equation by \left(2x-1\right)\left(2x+1\right), the least common multiple of 2x+1,2x-1.
4x-2-\left(2x+1\right)\times 2x=\left(2x-1\right)\left(2x+1\right)
Use the distributive property to multiply 2x-1 by 2.
4x-2-\left(4x+2\right)x=\left(2x-1\right)\left(2x+1\right)
Use the distributive property to multiply 2x+1 by 2.
4x-2-\left(4x^{2}+2x\right)=\left(2x-1\right)\left(2x+1\right)
Use the distributive property to multiply 4x+2 by x.
4x-2-4x^{2}-2x=\left(2x-1\right)\left(2x+1\right)
To find the opposite of 4x^{2}+2x, find the opposite of each term.
2x-2-4x^{2}=\left(2x-1\right)\left(2x+1\right)
Combine 4x and -2x to get 2x.
2x-2-4x^{2}=\left(2x\right)^{2}-1
Consider \left(2x-1\right)\left(2x+1\right). Multiplication can be transformed into difference of squares using the rule: \left(a-b\right)\left(a+b\right)=a^{2}-b^{2}. Square 1.
2x-2-4x^{2}=2^{2}x^{2}-1
Expand \left(2x\right)^{2}.
2x-2-4x^{2}=4x^{2}-1
Calculate 2 to the power of 2 and get 4.
2x-2-4x^{2}-4x^{2}=-1
Subtract 4x^{2} from both sides.
2x-2-8x^{2}=-1
Combine -4x^{2} and -4x^{2} to get -8x^{2}.
2x-8x^{2}=-1+2
Add 2 to both sides.
2x-8x^{2}=1
Add -1 and 2 to get 1.
-8x^{2}+2x=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{-8x^{2}+2x}{-8}=\frac{1}{-8}
Divide both sides by -8.
x^{2}+\frac{2}{-8}x=\frac{1}{-8}
Dividing by -8 undoes the multiplication by -8.
x^{2}-\frac{1}{4}x=\frac{1}{-8}
Reduce the fraction \frac{2}{-8} to lowest terms by extracting and canceling out 2.
x^{2}-\frac{1}{4}x=-\frac{1}{8}
Divide 1 by -8.
x^{2}-\frac{1}{4}x+\left(-\frac{1}{8}\right)^{2}=-\frac{1}{8}+\left(-\frac{1}{8}\right)^{2}
Divide -\frac{1}{4}, the coefficient of the x term, by 2 to get -\frac{1}{8}. Then add the square of -\frac{1}{8} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}-\frac{1}{4}x+\frac{1}{64}=-\frac{1}{8}+\frac{1}{64}
Square -\frac{1}{8} by squaring both the numerator and the denominator of the fraction.
x^{2}-\frac{1}{4}x+\frac{1}{64}=-\frac{7}{64}
Add -\frac{1}{8} to \frac{1}{64} by finding a common denominator and adding the numerators. Then reduce the fraction to lowest terms if possible.
\left(x-\frac{1}{8}\right)^{2}=-\frac{7}{64}
Factor x^{2}-\frac{1}{4}x+\frac{1}{64}. 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}{8}\right)^{2}}=\sqrt{-\frac{7}{64}}
Take the square root of both sides of the equation.
x-\frac{1}{8}=\frac{\sqrt{7}i}{8} x-\frac{1}{8}=-\frac{\sqrt{7}i}{8}
Simplify.
x=\frac{1+\sqrt{7}i}{8} x=\frac{-\sqrt{7}i+1}{8}
Add \frac{1}{8} 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}