How does \sqrt{1+((x^2)/(4-x^2))} simplify to 2 times\sqrt{1/(4-x^2)}?

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The expression \(\sqrt{1+\frac{x^2}{4-x^2}}\) simplifies to \(2\sqrt{\frac{1}{4-x^2}}\) by finding a common denominator. By rewriting the expression, it becomes \(\frac{4-x^2+x^2}{4-x^2}\), which simplifies to \(\frac{4}{4-x^2}\). Taking the square root of this fraction leads to \(\sqrt{\frac{4}{4-x^2}} = \frac{2}{\sqrt{4-x^2}}\). Thus, the simplification process reveals the relationship clearly.
Waggattack
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1.I can't figure out how the \sqrt{1+((x^2)/(4-x^2))} simplifies to 2 times\sqrt{1/(4-x^2)}


I have tried rewriting it in different ways, but I can't see how it simplifies. \sqrt{x^2 + 1/4-x^2}
 
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The first thing to do is find a common denominator. Then you will be able to zero out some terms. Then, using the property of a square root, the square root of a fraction is the same as the square root of the numerator over the square root of the denominator. This will give you the answer.
 
Waggattack said:
\sqrt{1+((x^2)/(4-x^2))} simplifies to 2 times \sqrt{1/(4-x^2)}

It may help to rewrite these in a form where you don't need the parentheses.

\sqrt{1+{{x^2}\over{4-x^2}}} simplifies to 2\sqrt{{{1}\over{4-x^2}}}
Does that make it easier?
 
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Hint: 1 in the square root, 1=\frac{4-x^2}{4-x^2}
 
In other words, write
1+\frac{x^2}{4-x^2}
as
\frac{4- x^2}{4- x^2}+ \frac{x^2}{4- x^2}
and add the fractions.
 
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