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Howdy! Here are a few very handy rules of algebra. These basic rules are useful for everything from figuring out your gas mileage to acing your next math test — or even solving equations from the far reaches of theoretical physics. Happy calculating!

Algebra Rule 22

Convert the root of a fraction into a fraction of two roots

$$\sqrt[n]{a \over b} = {\sqrt[n]{a} \over \sqrt[n]{b}}$$
Description:

To see how this works, we can use a similar trick to the rule above. If $x = \sqrt{a}$ and $y = \sqrt{b}$, then: $\sqrt{{a \over b}} = \sqrt{{x*x \over y*y}} = \sqrt{{x \over y}*{x \over y}} = \sqrt{{x \over y}^2} = {x \over y} = {\sqrt{a} \over \sqrt{b}}$

$$\sqrt[3]{8 \over 1} = 2 = {2\over 1} = {\sqrt[3]{8} \over \sqrt[3]{1}}$$
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