Solve for A
A=\frac{1}{9}\approx 0.111111111
A=0
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3A^{2}-\frac{1}{3}A=0
Subtract \frac{1}{3}A from both sides.
A\left(3A-\frac{1}{3}\right)=0
Factor out A.
A=0 A=\frac{1}{9}
To find equation solutions, solve A=0 and 3A-\frac{1}{3}=0.
3A^{2}-\frac{1}{3}A=0
Subtract \frac{1}{3}A from both sides.
A=\frac{-\left(-\frac{1}{3}\right)±\sqrt{\left(-\frac{1}{3}\right)^{2}}}{2\times 3}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 3 for a, -\frac{1}{3} for b, and 0 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
A=\frac{-\left(-\frac{1}{3}\right)±\frac{1}{3}}{2\times 3}
Take the square root of \left(-\frac{1}{3}\right)^{2}.
A=\frac{\frac{1}{3}±\frac{1}{3}}{2\times 3}
The opposite of -\frac{1}{3} is \frac{1}{3}.
A=\frac{\frac{1}{3}±\frac{1}{3}}{6}
Multiply 2 times 3.
A=\frac{\frac{2}{3}}{6}
Now solve the equation A=\frac{\frac{1}{3}±\frac{1}{3}}{6} when ± is plus. Add \frac{1}{3} to \frac{1}{3} by finding a common denominator and adding the numerators. Then reduce the fraction to lowest terms if possible.
A=\frac{1}{9}
Divide \frac{2}{3} by 6.
A=\frac{0}{6}
Now solve the equation A=\frac{\frac{1}{3}±\frac{1}{3}}{6} when ± is minus. Subtract \frac{1}{3} from \frac{1}{3} by finding a common denominator and subtracting the numerators. Then reduce the fraction to lowest terms if possible.
A=0
Divide 0 by 6.
A=\frac{1}{9} A=0
The equation is now solved.
3A^{2}-\frac{1}{3}A=0
Subtract \frac{1}{3}A from both sides.
\frac{3A^{2}-\frac{1}{3}A}{3}=\frac{0}{3}
Divide both sides by 3.
A^{2}+\left(-\frac{\frac{1}{3}}{3}\right)A=\frac{0}{3}
Dividing by 3 undoes the multiplication by 3.
A^{2}-\frac{1}{9}A=\frac{0}{3}
Divide -\frac{1}{3} by 3.
A^{2}-\frac{1}{9}A=0
Divide 0 by 3.
A^{2}-\frac{1}{9}A+\left(-\frac{1}{18}\right)^{2}=\left(-\frac{1}{18}\right)^{2}
Divide -\frac{1}{9}, the coefficient of the x term, by 2 to get -\frac{1}{18}. Then add the square of -\frac{1}{18} to both sides of the equation. This step makes the left hand side of the equation a perfect square.
A^{2}-\frac{1}{9}A+\frac{1}{324}=\frac{1}{324}
Square -\frac{1}{18} by squaring both the numerator and the denominator of the fraction.
\left(A-\frac{1}{18}\right)^{2}=\frac{1}{324}
Factor A^{2}-\frac{1}{9}A+\frac{1}{324}. 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(A-\frac{1}{18}\right)^{2}}=\sqrt{\frac{1}{324}}
Take the square root of both sides of the equation.
A-\frac{1}{18}=\frac{1}{18} A-\frac{1}{18}=-\frac{1}{18}
Simplify.
A=\frac{1}{9} A=0
Add \frac{1}{18} to both sides of the equation.
Examples
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{ x } ^ { 2 } - 4 x - 5 = 0
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4 \sin \theta \cos \theta = 2 \sin \theta
Linear equation
y = 3x + 4
Arithmetic
699 * 533
Matrix
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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
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