Solve for x
x=2\sqrt{3}\approx 3.464101615
x=-2\sqrt{3}\approx -3.464101615
Graph
Share
Copied to clipboard
x^{2}\times \frac{1}{2}=6
Multiply x and x to get x^{2}.
x^{2}=6\times 2
Multiply both sides by 2, the reciprocal of \frac{1}{2}.
x^{2}=12
Multiply 6 and 2 to get 12.
x=2\sqrt{3} x=-2\sqrt{3}
Take the square root of both sides of the equation.
x^{2}\times \frac{1}{2}=6
Multiply x and x to get x^{2}.
x^{2}\times \frac{1}{2}-6=0
Subtract 6 from both sides.
\frac{1}{2}x^{2}-6=0
Quadratic equations like this one, with an x^{2} term but no x term, can still be solved using the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}, once they are put in standard form: ax^{2}+bx+c=0.
x=\frac{0±\sqrt{0^{2}-4\times \frac{1}{2}\left(-6\right)}}{2\times \frac{1}{2}}
This equation is in standard form: ax^{2}+bx+c=0. Substitute \frac{1}{2} for a, 0 for b, and -6 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{0±\sqrt{-4\times \frac{1}{2}\left(-6\right)}}{2\times \frac{1}{2}}
Square 0.
x=\frac{0±\sqrt{-2\left(-6\right)}}{2\times \frac{1}{2}}
Multiply -4 times \frac{1}{2}.
x=\frac{0±\sqrt{12}}{2\times \frac{1}{2}}
Multiply -2 times -6.
x=\frac{0±2\sqrt{3}}{2\times \frac{1}{2}}
Take the square root of 12.
x=\frac{0±2\sqrt{3}}{1}
Multiply 2 times \frac{1}{2}.
x=2\sqrt{3}
Now solve the equation x=\frac{0±2\sqrt{3}}{1} when ± is plus.
x=-2\sqrt{3}
Now solve the equation x=\frac{0±2\sqrt{3}}{1} when ± is minus.
x=2\sqrt{3} x=-2\sqrt{3}
The equation is now solved.
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}