Solve for x
x=\frac{\sqrt{41}-3}{8}\approx 0.42539053
x=\frac{-\sqrt{41}-3}{8}\approx -1.17539053
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x^{2}-x^{2}\times 2+1-x^{2}=2x^{2}+4x-x-1
Multiply x and x to get x^{2}.
-x^{2}+1-x^{2}=2x^{2}+4x-x-1
Combine x^{2} and -x^{2}\times 2 to get -x^{2}.
-2x^{2}+1=2x^{2}+4x-x-1
Combine -x^{2} and -x^{2} to get -2x^{2}.
-2x^{2}+1=2x^{2}+3x-1
Combine 4x and -x to get 3x.
-2x^{2}+1-2x^{2}=3x-1
Subtract 2x^{2} from both sides.
-4x^{2}+1=3x-1
Combine -2x^{2} and -2x^{2} to get -4x^{2}.
-4x^{2}+1-3x=-1
Subtract 3x from both sides.
-4x^{2}+1-3x+1=0
Add 1 to both sides.
-4x^{2}+2-3x=0
Add 1 and 1 to get 2.
-4x^{2}-3x+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(-3\right)±\sqrt{\left(-3\right)^{2}-4\left(-4\right)\times 2}}{2\left(-4\right)}
This equation is in standard form: ax^{2}+bx+c=0. Substitute -4 for a, -3 for b, and 2 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-\left(-3\right)±\sqrt{9-4\left(-4\right)\times 2}}{2\left(-4\right)}
Square -3.
x=\frac{-\left(-3\right)±\sqrt{9+16\times 2}}{2\left(-4\right)}
Multiply -4 times -4.
x=\frac{-\left(-3\right)±\sqrt{9+32}}{2\left(-4\right)}
Multiply 16 times 2.
x=\frac{-\left(-3\right)±\sqrt{41}}{2\left(-4\right)}
Add 9 to 32.
x=\frac{3±\sqrt{41}}{2\left(-4\right)}
The opposite of -3 is 3.
x=\frac{3±\sqrt{41}}{-8}
Multiply 2 times -4.
x=\frac{\sqrt{41}+3}{-8}
Now solve the equation x=\frac{3±\sqrt{41}}{-8} when ± is plus. Add 3 to \sqrt{41}.
x=\frac{-\sqrt{41}-3}{8}
Divide 3+\sqrt{41} by -8.
x=\frac{3-\sqrt{41}}{-8}
Now solve the equation x=\frac{3±\sqrt{41}}{-8} when ± is minus. Subtract \sqrt{41} from 3.
x=\frac{\sqrt{41}-3}{8}
Divide 3-\sqrt{41} by -8.
x=\frac{-\sqrt{41}-3}{8} x=\frac{\sqrt{41}-3}{8}
The equation is now solved.
x^{2}-x^{2}\times 2+1-x^{2}=2x^{2}+4x-x-1
Multiply x and x to get x^{2}.
-x^{2}+1-x^{2}=2x^{2}+4x-x-1
Combine x^{2} and -x^{2}\times 2 to get -x^{2}.
-2x^{2}+1=2x^{2}+4x-x-1
Combine -x^{2} and -x^{2} to get -2x^{2}.
-2x^{2}+1=2x^{2}+3x-1
Combine 4x and -x to get 3x.
-2x^{2}+1-2x^{2}=3x-1
Subtract 2x^{2} from both sides.
-4x^{2}+1=3x-1
Combine -2x^{2} and -2x^{2} to get -4x^{2}.
-4x^{2}+1-3x=-1
Subtract 3x from both sides.
-4x^{2}-3x=-1-1
Subtract 1 from both sides.
-4x^{2}-3x=-2
Subtract 1 from -1 to get -2.
\frac{-4x^{2}-3x}{-4}=-\frac{2}{-4}
Divide both sides by -4.
x^{2}+\left(-\frac{3}{-4}\right)x=-\frac{2}{-4}
Dividing by -4 undoes the multiplication by -4.
x^{2}+\frac{3}{4}x=-\frac{2}{-4}
Divide -3 by -4.
x^{2}+\frac{3}{4}x=\frac{1}{2}
Reduce the fraction \frac{-2}{-4} to lowest terms by extracting and canceling out 2.
x^{2}+\frac{3}{4}x+\left(\frac{3}{8}\right)^{2}=\frac{1}{2}+\left(\frac{3}{8}\right)^{2}
Divide \frac{3}{4}, the coefficient of the x term, by 2 to get \frac{3}{8}. Then add the square of \frac{3}{8} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}+\frac{3}{4}x+\frac{9}{64}=\frac{1}{2}+\frac{9}{64}
Square \frac{3}{8} by squaring both the numerator and the denominator of the fraction.
x^{2}+\frac{3}{4}x+\frac{9}{64}=\frac{41}{64}
Add \frac{1}{2} to \frac{9}{64} by finding a common denominator and adding the numerators. Then reduce the fraction to lowest terms if possible.
\left(x+\frac{3}{8}\right)^{2}=\frac{41}{64}
Factor x^{2}+\frac{3}{4}x+\frac{9}{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{3}{8}\right)^{2}}=\sqrt{\frac{41}{64}}
Take the square root of both sides of the equation.
x+\frac{3}{8}=\frac{\sqrt{41}}{8} x+\frac{3}{8}=-\frac{\sqrt{41}}{8}
Simplify.
x=\frac{\sqrt{41}-3}{8} x=\frac{-\sqrt{41}-3}{8}
Subtract \frac{3}{8} 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}