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x=3
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\frac{1}{2}\left(6-x^{2}+2x\right)x+\frac{1}{2}\left(-x^{2}+2x+3\right)\left(3-x\right)-\frac{1}{2}\times 3\times 3=0
Add 3 and 3 to get 6.
\left(3+\frac{1}{2}\left(-x^{2}\right)+x\right)x+\frac{1}{2}\left(-x^{2}+2x+3\right)\left(3-x\right)-\frac{1}{2}\times 3\times 3=0
Use the distributive property to multiply \frac{1}{2} by 6-x^{2}+2x.
3x+\frac{1}{2}\left(-x^{2}\right)x+x^{2}+\frac{1}{2}\left(-x^{2}+2x+3\right)\left(3-x\right)-\frac{1}{2}\times 3\times 3=0
Use the distributive property to multiply 3+\frac{1}{2}\left(-x^{2}\right)+x by x.
3x+\frac{1}{2}\left(-x^{2}\right)x+x^{2}+\left(\frac{1}{2}\left(-x^{2}\right)+x+\frac{3}{2}\right)\left(3-x\right)-\frac{1}{2}\times 3\times 3=0
Use the distributive property to multiply \frac{1}{2} by -x^{2}+2x+3.
3x+\frac{1}{2}\left(-x^{2}\right)x+x^{2}+\frac{3}{2}\left(-x^{2}\right)-\frac{1}{2}\left(-x^{2}\right)x+\frac{3}{2}x-x^{2}+\frac{9}{2}-\frac{1}{2}\times 3\times 3=0
Use the distributive property to multiply \frac{1}{2}\left(-x^{2}\right)+x+\frac{3}{2} by 3-x and combine like terms.
3x+\frac{1}{2}\left(-x^{2}\right)x+x^{2}+\frac{3}{2}\left(-x^{2}\right)+\frac{1}{2}x^{2}x+\frac{3}{2}x-x^{2}+\frac{9}{2}-\frac{1}{2}\times 3\times 3=0
Multiply -\frac{1}{2} and -1 to get \frac{1}{2}.
3x+\frac{1}{2}\left(-x^{2}\right)x+x^{2}+\frac{3}{2}\left(-x^{2}\right)+\frac{1}{2}x^{3}+\frac{3}{2}x-x^{2}+\frac{9}{2}-\frac{1}{2}\times 3\times 3=0
To multiply powers of the same base, add their exponents. Add 2 and 1 to get 3.
\frac{9}{2}x+\frac{1}{2}\left(-x^{2}\right)x+x^{2}+\frac{3}{2}\left(-x^{2}\right)+\frac{1}{2}x^{3}-x^{2}+\frac{9}{2}-\frac{1}{2}\times 3\times 3=0
Combine 3x and \frac{3}{2}x to get \frac{9}{2}x.
\frac{9}{2}x+\frac{1}{2}\left(-x^{2}\right)x+\frac{3}{2}\left(-x^{2}\right)+\frac{1}{2}x^{3}+\frac{9}{2}-\frac{1}{2}\times 3\times 3=0
Combine x^{2} and -x^{2} to get 0.
\frac{9}{2}x+\frac{1}{2}\left(-x^{2}\right)x+\frac{3}{2}\left(-x^{2}\right)+\frac{1}{2}x^{3}+\frac{9}{2}-\frac{3}{2}\times 3=0
Multiply \frac{1}{2} and 3 to get \frac{3}{2}.
\frac{9}{2}x+\frac{1}{2}\left(-x^{2}\right)x+\frac{3}{2}\left(-x^{2}\right)+\frac{1}{2}x^{3}+\frac{9}{2}-\frac{9}{2}=0
Multiply \frac{3}{2} and 3 to get \frac{9}{2}.
\frac{9}{2}x+\frac{1}{2}\left(-x^{2}\right)x+\frac{3}{2}\left(-x^{2}\right)+\frac{1}{2}x^{3}=0
Subtract \frac{9}{2} from \frac{9}{2} to get 0.
\frac{9}{2}x+\frac{1}{2}\left(-1\right)x^{3}+\frac{3}{2}\left(-1\right)x^{2}+\frac{1}{2}x^{3}=0
To multiply powers of the same base, add their exponents. Add 2 and 1 to get 3.
\frac{9}{2}x-\frac{1}{2}x^{3}+\frac{3}{2}\left(-1\right)x^{2}+\frac{1}{2}x^{3}=0
Multiply \frac{1}{2} and -1 to get -\frac{1}{2}.
\frac{9}{2}x-\frac{1}{2}x^{3}-\frac{3}{2}x^{2}+\frac{1}{2}x^{3}=0
Multiply \frac{3}{2} and -1 to get -\frac{3}{2}.
\frac{9}{2}x-\frac{3}{2}x^{2}=0
Combine -\frac{1}{2}x^{3} and \frac{1}{2}x^{3} to get 0.
x\left(\frac{9}{2}-\frac{3}{2}x\right)=0
Factor out x.
x=0 x=3
To find equation solutions, solve x=0 and \frac{9-3x}{2}=0.
\frac{1}{2}\left(6-x^{2}+2x\right)x+\frac{1}{2}\left(-x^{2}+2x+3\right)\left(3-x\right)-\frac{1}{2}\times 3\times 3=0
Add 3 and 3 to get 6.
\left(3+\frac{1}{2}\left(-x^{2}\right)+x\right)x+\frac{1}{2}\left(-x^{2}+2x+3\right)\left(3-x\right)-\frac{1}{2}\times 3\times 3=0
Use the distributive property to multiply \frac{1}{2} by 6-x^{2}+2x.
3x+\frac{1}{2}\left(-x^{2}\right)x+x^{2}+\frac{1}{2}\left(-x^{2}+2x+3\right)\left(3-x\right)-\frac{1}{2}\times 3\times 3=0
Use the distributive property to multiply 3+\frac{1}{2}\left(-x^{2}\right)+x by x.
3x+\frac{1}{2}\left(-x^{2}\right)x+x^{2}+\left(\frac{1}{2}\left(-x^{2}\right)+x+\frac{3}{2}\right)\left(3-x\right)-\frac{1}{2}\times 3\times 3=0
Use the distributive property to multiply \frac{1}{2} by -x^{2}+2x+3.
3x+\frac{1}{2}\left(-x^{2}\right)x+x^{2}+\frac{3}{2}\left(-x^{2}\right)-\frac{1}{2}\left(-x^{2}\right)x+\frac{3}{2}x-x^{2}+\frac{9}{2}-\frac{1}{2}\times 3\times 3=0
Use the distributive property to multiply \frac{1}{2}\left(-x^{2}\right)+x+\frac{3}{2} by 3-x and combine like terms.
3x+\frac{1}{2}\left(-x^{2}\right)x+x^{2}+\frac{3}{2}\left(-x^{2}\right)+\frac{1}{2}x^{2}x+\frac{3}{2}x-x^{2}+\frac{9}{2}-\frac{1}{2}\times 3\times 3=0
Multiply -\frac{1}{2} and -1 to get \frac{1}{2}.
3x+\frac{1}{2}\left(-x^{2}\right)x+x^{2}+\frac{3}{2}\left(-x^{2}\right)+\frac{1}{2}x^{3}+\frac{3}{2}x-x^{2}+\frac{9}{2}-\frac{1}{2}\times 3\times 3=0
To multiply powers of the same base, add their exponents. Add 2 and 1 to get 3.
\frac{9}{2}x+\frac{1}{2}\left(-x^{2}\right)x+x^{2}+\frac{3}{2}\left(-x^{2}\right)+\frac{1}{2}x^{3}-x^{2}+\frac{9}{2}-\frac{1}{2}\times 3\times 3=0
Combine 3x and \frac{3}{2}x to get \frac{9}{2}x.
\frac{9}{2}x+\frac{1}{2}\left(-x^{2}\right)x+\frac{3}{2}\left(-x^{2}\right)+\frac{1}{2}x^{3}+\frac{9}{2}-\frac{1}{2}\times 3\times 3=0
Combine x^{2} and -x^{2} to get 0.
\frac{9}{2}x+\frac{1}{2}\left(-x^{2}\right)x+\frac{3}{2}\left(-x^{2}\right)+\frac{1}{2}x^{3}+\frac{9}{2}-\frac{3}{2}\times 3=0
Multiply \frac{1}{2} and 3 to get \frac{3}{2}.
\frac{9}{2}x+\frac{1}{2}\left(-x^{2}\right)x+\frac{3}{2}\left(-x^{2}\right)+\frac{1}{2}x^{3}+\frac{9}{2}-\frac{9}{2}=0
Multiply \frac{3}{2} and 3 to get \frac{9}{2}.
\frac{9}{2}x+\frac{1}{2}\left(-x^{2}\right)x+\frac{3}{2}\left(-x^{2}\right)+\frac{1}{2}x^{3}=0
Subtract \frac{9}{2} from \frac{9}{2} to get 0.
\frac{9}{2}x+\frac{1}{2}\left(-1\right)x^{3}+\frac{3}{2}\left(-1\right)x^{2}+\frac{1}{2}x^{3}=0
To multiply powers of the same base, add their exponents. Add 2 and 1 to get 3.
\frac{9}{2}x-\frac{1}{2}x^{3}+\frac{3}{2}\left(-1\right)x^{2}+\frac{1}{2}x^{3}=0
Multiply \frac{1}{2} and -1 to get -\frac{1}{2}.
\frac{9}{2}x-\frac{1}{2}x^{3}-\frac{3}{2}x^{2}+\frac{1}{2}x^{3}=0
Multiply \frac{3}{2} and -1 to get -\frac{3}{2}.
\frac{9}{2}x-\frac{3}{2}x^{2}=0
Combine -\frac{1}{2}x^{3} and \frac{1}{2}x^{3} to get 0.
-\frac{3}{2}x^{2}+\frac{9}{2}x=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{-\frac{9}{2}±\sqrt{\left(\frac{9}{2}\right)^{2}}}{2\left(-\frac{3}{2}\right)}
This equation is in standard form: ax^{2}+bx+c=0. Substitute -\frac{3}{2} for a, \frac{9}{2} for b, and 0 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{-\frac{9}{2}±\frac{9}{2}}{2\left(-\frac{3}{2}\right)}
Take the square root of \left(\frac{9}{2}\right)^{2}.
x=\frac{-\frac{9}{2}±\frac{9}{2}}{-3}
Multiply 2 times -\frac{3}{2}.
x=\frac{0}{-3}
Now solve the equation x=\frac{-\frac{9}{2}±\frac{9}{2}}{-3} when ± is plus. Add -\frac{9}{2} to \frac{9}{2} by finding a common denominator and adding the numerators. Then reduce the fraction to lowest terms if possible.
x=0
Divide 0 by -3.
x=-\frac{9}{-3}
Now solve the equation x=\frac{-\frac{9}{2}±\frac{9}{2}}{-3} when ± is minus. Subtract \frac{9}{2} from -\frac{9}{2} by finding a common denominator and subtracting the numerators. Then reduce the fraction to lowest terms if possible.
x=3
Divide -9 by -3.
x=0 x=3
The equation is now solved.
\frac{1}{2}\left(6-x^{2}+2x\right)x+\frac{1}{2}\left(-x^{2}+2x+3\right)\left(3-x\right)-\frac{1}{2}\times 3\times 3=0
Add 3 and 3 to get 6.
\left(3+\frac{1}{2}\left(-x^{2}\right)+x\right)x+\frac{1}{2}\left(-x^{2}+2x+3\right)\left(3-x\right)-\frac{1}{2}\times 3\times 3=0
Use the distributive property to multiply \frac{1}{2} by 6-x^{2}+2x.
3x+\frac{1}{2}\left(-x^{2}\right)x+x^{2}+\frac{1}{2}\left(-x^{2}+2x+3\right)\left(3-x\right)-\frac{1}{2}\times 3\times 3=0
Use the distributive property to multiply 3+\frac{1}{2}\left(-x^{2}\right)+x by x.
3x+\frac{1}{2}\left(-x^{2}\right)x+x^{2}+\left(\frac{1}{2}\left(-x^{2}\right)+x+\frac{3}{2}\right)\left(3-x\right)-\frac{1}{2}\times 3\times 3=0
Use the distributive property to multiply \frac{1}{2} by -x^{2}+2x+3.
3x+\frac{1}{2}\left(-x^{2}\right)x+x^{2}+\frac{3}{2}\left(-x^{2}\right)-\frac{1}{2}\left(-x^{2}\right)x+\frac{3}{2}x-x^{2}+\frac{9}{2}-\frac{1}{2}\times 3\times 3=0
Use the distributive property to multiply \frac{1}{2}\left(-x^{2}\right)+x+\frac{3}{2} by 3-x and combine like terms.
3x+\frac{1}{2}\left(-x^{2}\right)x+x^{2}+\frac{3}{2}\left(-x^{2}\right)+\frac{1}{2}x^{2}x+\frac{3}{2}x-x^{2}+\frac{9}{2}-\frac{1}{2}\times 3\times 3=0
Multiply -\frac{1}{2} and -1 to get \frac{1}{2}.
3x+\frac{1}{2}\left(-x^{2}\right)x+x^{2}+\frac{3}{2}\left(-x^{2}\right)+\frac{1}{2}x^{3}+\frac{3}{2}x-x^{2}+\frac{9}{2}-\frac{1}{2}\times 3\times 3=0
To multiply powers of the same base, add their exponents. Add 2 and 1 to get 3.
\frac{9}{2}x+\frac{1}{2}\left(-x^{2}\right)x+x^{2}+\frac{3}{2}\left(-x^{2}\right)+\frac{1}{2}x^{3}-x^{2}+\frac{9}{2}-\frac{1}{2}\times 3\times 3=0
Combine 3x and \frac{3}{2}x to get \frac{9}{2}x.
\frac{9}{2}x+\frac{1}{2}\left(-x^{2}\right)x+\frac{3}{2}\left(-x^{2}\right)+\frac{1}{2}x^{3}+\frac{9}{2}-\frac{1}{2}\times 3\times 3=0
Combine x^{2} and -x^{2} to get 0.
\frac{9}{2}x+\frac{1}{2}\left(-x^{2}\right)x+\frac{3}{2}\left(-x^{2}\right)+\frac{1}{2}x^{3}+\frac{9}{2}-\frac{3}{2}\times 3=0
Multiply \frac{1}{2} and 3 to get \frac{3}{2}.
\frac{9}{2}x+\frac{1}{2}\left(-x^{2}\right)x+\frac{3}{2}\left(-x^{2}\right)+\frac{1}{2}x^{3}+\frac{9}{2}-\frac{9}{2}=0
Multiply \frac{3}{2} and 3 to get \frac{9}{2}.
\frac{9}{2}x+\frac{1}{2}\left(-x^{2}\right)x+\frac{3}{2}\left(-x^{2}\right)+\frac{1}{2}x^{3}=0
Subtract \frac{9}{2} from \frac{9}{2} to get 0.
\frac{9}{2}x+\frac{1}{2}\left(-1\right)x^{3}+\frac{3}{2}\left(-1\right)x^{2}+\frac{1}{2}x^{3}=0
To multiply powers of the same base, add their exponents. Add 2 and 1 to get 3.
\frac{9}{2}x-\frac{1}{2}x^{3}+\frac{3}{2}\left(-1\right)x^{2}+\frac{1}{2}x^{3}=0
Multiply \frac{1}{2} and -1 to get -\frac{1}{2}.
\frac{9}{2}x-\frac{1}{2}x^{3}-\frac{3}{2}x^{2}+\frac{1}{2}x^{3}=0
Multiply \frac{3}{2} and -1 to get -\frac{3}{2}.
\frac{9}{2}x-\frac{3}{2}x^{2}=0
Combine -\frac{1}{2}x^{3} and \frac{1}{2}x^{3} to get 0.
-\frac{3}{2}x^{2}+\frac{9}{2}x=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.
\frac{-\frac{3}{2}x^{2}+\frac{9}{2}x}{-\frac{3}{2}}=\frac{0}{-\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}+\frac{\frac{9}{2}}{-\frac{3}{2}}x=\frac{0}{-\frac{3}{2}}
Dividing by -\frac{3}{2} undoes the multiplication by -\frac{3}{2}.
x^{2}-3x=\frac{0}{-\frac{3}{2}}
Divide \frac{9}{2} by -\frac{3}{2} by multiplying \frac{9}{2} by the reciprocal of -\frac{3}{2}.
x^{2}-3x=0
Divide 0 by -\frac{3}{2} by multiplying 0 by the reciprocal of -\frac{3}{2}.
x^{2}-3x+\left(-\frac{3}{2}\right)^{2}=\left(-\frac{3}{2}\right)^{2}
Divide -3, the coefficient of the x term, by 2 to get -\frac{3}{2}. Then add the square of -\frac{3}{2} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
x^{2}-3x+\frac{9}{4}=\frac{9}{4}
Square -\frac{3}{2} by squaring both the numerator and the denominator of the fraction.
\left(x-\frac{3}{2}\right)^{2}=\frac{9}{4}
Factor x^{2}-3x+\frac{9}{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-\frac{3}{2}\right)^{2}}=\sqrt{\frac{9}{4}}
Take the square root of both sides of the equation.
x-\frac{3}{2}=\frac{3}{2} x-\frac{3}{2}=-\frac{3}{2}
Simplify.
x=3 x=0
Add \frac{3}{2} 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}