Solve for x
x=\frac{\sqrt{21}}{21}\approx 0.21821789
x=-\frac{\sqrt{21}}{21}\approx -0.21821789
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xx+1=22xx
Variable x cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by x.
x^{2}+1=22xx
Multiply x and x to get x^{2}.
x^{2}+1=22x^{2}
Multiply x and x to get x^{2}.
x^{2}+1-22x^{2}=0
Subtract 22x^{2} from both sides.
-21x^{2}+1=0
Combine x^{2} and -22x^{2} to get -21x^{2}.
-21x^{2}=-1
Subtract 1 from both sides. Anything subtracted from zero gives its negation.
x^{2}=\frac{-1}{-21}
Divide both sides by -21.
x^{2}=\frac{1}{21}
Fraction \frac{-1}{-21} can be simplified to \frac{1}{21} by removing the negative sign from both the numerator and the denominator.
x=\frac{\sqrt{21}}{21} x=-\frac{\sqrt{21}}{21}
Take the square root of both sides of the equation.
xx+1=22xx
Variable x cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by x.
x^{2}+1=22xx
Multiply x and x to get x^{2}.
x^{2}+1=22x^{2}
Multiply x and x to get x^{2}.
x^{2}+1-22x^{2}=0
Subtract 22x^{2} from both sides.
-21x^{2}+1=0
Combine x^{2} and -22x^{2} to get -21x^{2}.
x=\frac{0±\sqrt{0^{2}-4\left(-21\right)}}{2\left(-21\right)}
This equation is in standard form: ax^{2}+bx+c=0. Substitute -21 for a, 0 for b, and 1 for c in the quadratic formula, \frac{-b±\sqrt{b^{2}-4ac}}{2a}.
x=\frac{0±\sqrt{-4\left(-21\right)}}{2\left(-21\right)}
Square 0.
x=\frac{0±\sqrt{84}}{2\left(-21\right)}
Multiply -4 times -21.
x=\frac{0±2\sqrt{21}}{2\left(-21\right)}
Take the square root of 84.
x=\frac{0±2\sqrt{21}}{-42}
Multiply 2 times -21.
x=-\frac{\sqrt{21}}{21}
Now solve the equation x=\frac{0±2\sqrt{21}}{-42} when ± is plus.
x=\frac{\sqrt{21}}{21}
Now solve the equation x=\frac{0±2\sqrt{21}}{-42} when ± is minus.
x=-\frac{\sqrt{21}}{21} x=\frac{\sqrt{21}}{21}
The equation is now solved.
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Limits
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