Solve for x
x=\frac{\sqrt{2}}{2}\approx 0.707106781
x=-\frac{\sqrt{2}}{2}\approx -0.707106781
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4x^{2}=2
Add 2 to both sides. Anything plus zero gives itself.
x^{2}=\frac{2}{4}
Divide both sides by 4.
x^{2}=\frac{1}{2}
Reduce the fraction \frac{2}{4} to lowest terms by extracting and canceling out 2.
x=\frac{\sqrt{2}}{2} x=-\frac{\sqrt{2}}{2}
Take the square root of both sides of the equation.
4x^{2}-2=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 4\left(-2\right)}}{2\times 4}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 4 for a, 0 for b, and -2 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{0±\sqrt{-4\times 4\left(-2\right)}}{2\times 4}
Square 0.
x=\frac{0±\sqrt{-16\left(-2\right)}}{2\times 4}
Multiply -4 times 4.
x=\frac{0±\sqrt{32}}{2\times 4}
Multiply -16 times -2.
x=\frac{0±4\sqrt{2}}{2\times 4}
Take the square root of 32.
x=\frac{0±4\sqrt{2}}{8}
Multiply 2 times 4.
x=\frac{\sqrt{2}}{2}
Now solve the equation x=\frac{0±4\sqrt{2}}{8} when ± is plus.
x=-\frac{\sqrt{2}}{2}
Now solve the equation x=\frac{0±4\sqrt{2}}{8} when ± is minus.
x=\frac{\sqrt{2}}{2} x=-\frac{\sqrt{2}}{2}
The equation is now solved.
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
\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}