Solve for m (complex solution)
m=\sqrt{22}-4\approx 0.69041576
m=-\left(\sqrt{22}+4\right)\approx -8.69041576
Solve for m
m=\sqrt{22}-4\approx 0.69041576
m=-\sqrt{22}-4\approx -8.69041576
Quiz
Quadratic Equation
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\frac { m ^ { 2 } } { 4 } + 2 m - 1 = \frac { 2 } { 4 }
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\frac{1}{4}m^{2}+2m-1=\frac{1}{2}
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.
\frac{1}{4}m^{2}+2m-1-\frac{1}{2}=\frac{1}{2}-\frac{1}{2}
Subtract \frac{1}{2} from both sides of the equation.
\frac{1}{4}m^{2}+2m-1-\frac{1}{2}=0
Subtracting \frac{1}{2} from itself leaves 0.
\frac{1}{4}m^{2}+2m-\frac{3}{2}=0
Subtract \frac{1}{2} from -1.
m=\frac{-2±\sqrt{2^{2}-4\times \frac{1}{4}\left(-\frac{3}{2}\right)}}{2\times \frac{1}{4}}
This equation is in standard form: ax^{2}+bx+c=0. Substitute \frac{1}{4} for a, 2 for b, and -\frac{3}{2} for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
m=\frac{-2±\sqrt{4-4\times \frac{1}{4}\left(-\frac{3}{2}\right)}}{2\times \frac{1}{4}}
Square 2.
m=\frac{-2±\sqrt{4-\left(-\frac{3}{2}\right)}}{2\times \frac{1}{4}}
Multiply -4 times \frac{1}{4}.
m=\frac{-2±\sqrt{4+\frac{3}{2}}}{2\times \frac{1}{4}}
Multiply -1 times -\frac{3}{2}.
m=\frac{-2±\sqrt{\frac{11}{2}}}{2\times \frac{1}{4}}
Add 4 to \frac{3}{2}.
m=\frac{-2±\frac{\sqrt{22}}{2}}{2\times \frac{1}{4}}
Take the square root of \frac{11}{2}.
m=\frac{-2±\frac{\sqrt{22}}{2}}{\frac{1}{2}}
Multiply 2 times \frac{1}{4}.
m=\frac{\frac{\sqrt{22}}{2}-2}{\frac{1}{2}}
Now solve the equation m=\frac{-2±\frac{\sqrt{22}}{2}}{\frac{1}{2}} when ± is plus. Add -2 to \frac{\sqrt{22}}{2}.
m=\sqrt{22}-4
Divide -2+\frac{\sqrt{22}}{2} by \frac{1}{2} by multiplying -2+\frac{\sqrt{22}}{2} by the reciprocal of \frac{1}{2}.
m=\frac{-\frac{\sqrt{22}}{2}-2}{\frac{1}{2}}
Now solve the equation m=\frac{-2±\frac{\sqrt{22}}{2}}{\frac{1}{2}} when ± is minus. Subtract \frac{\sqrt{22}}{2} from -2.
m=-\sqrt{22}-4
Divide -2-\frac{\sqrt{22}}{2} by \frac{1}{2} by multiplying -2-\frac{\sqrt{22}}{2} by the reciprocal of \frac{1}{2}.
m=\sqrt{22}-4 m=-\sqrt{22}-4
The equation is now solved.
\frac{1}{4}m^{2}+2m-1=\frac{1}{2}
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{1}{4}m^{2}+2m-1-\left(-1\right)=\frac{1}{2}-\left(-1\right)
Add 1 to both sides of the equation.
\frac{1}{4}m^{2}+2m=\frac{1}{2}-\left(-1\right)
Subtracting -1 from itself leaves 0.
\frac{1}{4}m^{2}+2m=\frac{3}{2}
Subtract -1 from \frac{1}{2}.
\frac{\frac{1}{4}m^{2}+2m}{\frac{1}{4}}=\frac{\frac{3}{2}}{\frac{1}{4}}
Multiply both sides by 4.
m^{2}+\frac{2}{\frac{1}{4}}m=\frac{\frac{3}{2}}{\frac{1}{4}}
Dividing by \frac{1}{4} undoes the multiplication by \frac{1}{4}.
m^{2}+8m=\frac{\frac{3}{2}}{\frac{1}{4}}
Divide 2 by \frac{1}{4} by multiplying 2 by the reciprocal of \frac{1}{4}.
m^{2}+8m=6
Divide \frac{3}{2} by \frac{1}{4} by multiplying \frac{3}{2} by the reciprocal of \frac{1}{4}.
m^{2}+8m+4^{2}=6+4^{2}
Divide 8, the coefficient of the x term, by 2 to get 4. Then add the square of 4 to both sides of the equation. This step makes the left hand side of the equation a perfect square.
m^{2}+8m+16=6+16
Square 4.
m^{2}+8m+16=22
Add 6 to 16.
\left(m+4\right)^{2}=22
Factor m^{2}+8m+16. 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(m+4\right)^{2}}=\sqrt{22}
Take the square root of both sides of the equation.
m+4=\sqrt{22} m+4=-\sqrt{22}
Simplify.
m=\sqrt{22}-4 m=-\sqrt{22}-4
Subtract 4 from both sides of the equation.
\frac{1}{4}m^{2}+2m-1=\frac{1}{2}
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.
\frac{1}{4}m^{2}+2m-1-\frac{1}{2}=\frac{1}{2}-\frac{1}{2}
Subtract \frac{1}{2} from both sides of the equation.
\frac{1}{4}m^{2}+2m-1-\frac{1}{2}=0
Subtracting \frac{1}{2} from itself leaves 0.
\frac{1}{4}m^{2}+2m-\frac{3}{2}=0
Subtract \frac{1}{2} from -1.
m=\frac{-2±\sqrt{2^{2}-4\times \frac{1}{4}\left(-\frac{3}{2}\right)}}{2\times \frac{1}{4}}
This equation is in standard form: ax^{2}+bx+c=0. Substitute \frac{1}{4} for a, 2 for b, and -\frac{3}{2} for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
m=\frac{-2±\sqrt{4-4\times \frac{1}{4}\left(-\frac{3}{2}\right)}}{2\times \frac{1}{4}}
Square 2.
m=\frac{-2±\sqrt{4-\left(-\frac{3}{2}\right)}}{2\times \frac{1}{4}}
Multiply -4 times \frac{1}{4}.
m=\frac{-2±\sqrt{4+\frac{3}{2}}}{2\times \frac{1}{4}}
Multiply -1 times -\frac{3}{2}.
m=\frac{-2±\sqrt{\frac{11}{2}}}{2\times \frac{1}{4}}
Add 4 to \frac{3}{2}.
m=\frac{-2±\frac{\sqrt{22}}{2}}{2\times \frac{1}{4}}
Take the square root of \frac{11}{2}.
m=\frac{-2±\frac{\sqrt{22}}{2}}{\frac{1}{2}}
Multiply 2 times \frac{1}{4}.
m=\frac{\frac{\sqrt{22}}{2}-2}{\frac{1}{2}}
Now solve the equation m=\frac{-2±\frac{\sqrt{22}}{2}}{\frac{1}{2}} when ± is plus. Add -2 to \frac{\sqrt{22}}{2}.
m=\sqrt{22}-4
Divide -2+\frac{\sqrt{22}}{2} by \frac{1}{2} by multiplying -2+\frac{\sqrt{22}}{2} by the reciprocal of \frac{1}{2}.
m=\frac{-\frac{\sqrt{22}}{2}-2}{\frac{1}{2}}
Now solve the equation m=\frac{-2±\frac{\sqrt{22}}{2}}{\frac{1}{2}} when ± is minus. Subtract \frac{\sqrt{22}}{2} from -2.
m=-\sqrt{22}-4
Divide -2-\frac{\sqrt{22}}{2} by \frac{1}{2} by multiplying -2-\frac{\sqrt{22}}{2} by the reciprocal of \frac{1}{2}.
m=\sqrt{22}-4 m=-\sqrt{22}-4
The equation is now solved.
\frac{1}{4}m^{2}+2m-1=\frac{1}{2}
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{1}{4}m^{2}+2m-1-\left(-1\right)=\frac{1}{2}-\left(-1\right)
Add 1 to both sides of the equation.
\frac{1}{4}m^{2}+2m=\frac{1}{2}-\left(-1\right)
Subtracting -1 from itself leaves 0.
\frac{1}{4}m^{2}+2m=\frac{3}{2}
Subtract -1 from \frac{1}{2}.
\frac{\frac{1}{4}m^{2}+2m}{\frac{1}{4}}=\frac{\frac{3}{2}}{\frac{1}{4}}
Multiply both sides by 4.
m^{2}+\frac{2}{\frac{1}{4}}m=\frac{\frac{3}{2}}{\frac{1}{4}}
Dividing by \frac{1}{4} undoes the multiplication by \frac{1}{4}.
m^{2}+8m=\frac{\frac{3}{2}}{\frac{1}{4}}
Divide 2 by \frac{1}{4} by multiplying 2 by the reciprocal of \frac{1}{4}.
m^{2}+8m=6
Divide \frac{3}{2} by \frac{1}{4} by multiplying \frac{3}{2} by the reciprocal of \frac{1}{4}.
m^{2}+8m+4^{2}=6+4^{2}
Divide 8, the coefficient of the x term, by 2 to get 4. Then add the square of 4 to both sides of the equation. This step makes the left hand side of the equation a perfect square.
m^{2}+8m+16=6+16
Square 4.
m^{2}+8m+16=22
Add 6 to 16.
\left(m+4\right)^{2}=22
Factor m^{2}+8m+16. 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(m+4\right)^{2}}=\sqrt{22}
Take the square root of both sides of the equation.
m+4=\sqrt{22} m+4=-\sqrt{22}
Simplify.
m=\sqrt{22}-4 m=-\sqrt{22}-4
Subtract 4 from both sides of the equation.
Examples
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{ x } ^ { 2 } - 4 x - 5 = 0
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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}