Solve for a
a=2
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a=2\sqrt{a^{2}-3}
Variable a cannot be equal to 0 since division by zero is not defined. Multiply both sides of the equation by 2a, the least common multiple of 2,a.
a-2\sqrt{a^{2}-3}=0
Subtract 2\sqrt{a^{2}-3} from both sides.
-2\sqrt{a^{2}-3}=-a
Subtract a from both sides of the equation.
\left(-2\sqrt{a^{2}-3}\right)^{2}=\left(-a\right)^{2}
Square both sides of the equation.
\left(-2\right)^{2}\left(\sqrt{a^{2}-3}\right)^{2}=\left(-a\right)^{2}
Expand \left(-2\sqrt{a^{2}-3}\right)^{2}.
4\left(\sqrt{a^{2}-3}\right)^{2}=\left(-a\right)^{2}
Calculate -2 to the power of 2 and get 4.
4\left(a^{2}-3\right)=\left(-a\right)^{2}
Calculate \sqrt{a^{2}-3} to the power of 2 and get a^{2}-3.
4a^{2}-12=\left(-a\right)^{2}
Use the distributive property to multiply 4 by a^{2}-3.
4a^{2}-12=\left(-1\right)^{2}a^{2}
Expand \left(-a\right)^{2}.
4a^{2}-12=1a^{2}
Calculate -1 to the power of 2 and get 1.
4a^{2}-12-a^{2}=0
Subtract 1a^{2} from both sides.
3a^{2}-12=0
Combine 4a^{2} and -a^{2} to get 3a^{2}.
a^{2}-4=0
Divide both sides by 3.
\left(a-2\right)\left(a+2\right)=0
Consider a^{2}-4. Rewrite a^{2}-4 as a^{2}-2^{2}. The difference of squares can be factored using the rule: a^{2}-b^{2}=\left(a-b\right)\left(a+b\right).
a=2 a=-2
To find equation solutions, solve a-2=0 and a+2=0.
\frac{1}{2}=\frac{\sqrt{2^{2}-3}}{2}
Substitute 2 for a in the equation \frac{1}{2}=\frac{\sqrt{a^{2}-3}}{a}.
\frac{1}{2}=\frac{1}{2}
Simplify. The value a=2 satisfies the equation.
\frac{1}{2}=\frac{\sqrt{\left(-2\right)^{2}-3}}{-2}
Substitute -2 for a in the equation \frac{1}{2}=\frac{\sqrt{a^{2}-3}}{a}.
\frac{1}{2}=-\frac{1}{2}
Simplify. The value a=-2 does not satisfy the equation because the left and the right hand side have opposite signs.
a=2
Equation -2\sqrt{a^{2}-3}=-a has a unique solution.
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