Solve for x
x=\frac{2\sqrt{5}}{5}\approx 0.894427191
x=-\frac{2\sqrt{5}}{5}\approx -0.894427191
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5xx=4
Variable x cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by x.
5x^{2}=4
Multiply x and x to get x^{2}.
x^{2}=\frac{4}{5}
Divide both sides by 5.
x=\frac{2\sqrt{5}}{5} x=-\frac{2\sqrt{5}}{5}
Take the square root of both sides of the equation.
5xx=4
Variable x cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by x.
5x^{2}=4
Multiply x and x to get x^{2}.
5x^{2}-4=0
Subtract 4 from both sides.
x=\frac{0±\sqrt{0^{2}-4\times 5\left(-4\right)}}{2\times 5}
This equation is in standard form: ax^{2}+bx+c=0. Substitute 5 for a, 0 for b, and -4 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{0±\sqrt{-4\times 5\left(-4\right)}}{2\times 5}
Square 0.
x=\frac{0±\sqrt{-20\left(-4\right)}}{2\times 5}
Multiply -4 times 5.
x=\frac{0±\sqrt{80}}{2\times 5}
Multiply -20 times -4.
x=\frac{0±4\sqrt{5}}{2\times 5}
Take the square root of 80.
x=\frac{0±4\sqrt{5}}{10}
Multiply 2 times 5.
x=\frac{2\sqrt{5}}{5}
Now solve the equation x=\frac{0±4\sqrt{5}}{10} when ± is plus.
x=-\frac{2\sqrt{5}}{5}
Now solve the equation x=\frac{0±4\sqrt{5}}{10} when ± is minus.
x=\frac{2\sqrt{5}}{5} x=-\frac{2\sqrt{5}}{5}
The equation is now solved.
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Matrix
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Simultaneous equation
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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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