`sqrt(x/(2x+1)`

`=sqrtx/(sqrt(2x+1))xx(sqrt(2x+1))/(sqrt(2x+1))`

`=(sqrt(x)sqrt(2x+1))/(2x+1)`

We can see that the denominator no longer has a radical.

In the days before calculators, it was important to be able to rationalise a denominator like this. You can see more examples of this process in 5. Muliplication and Division of Radicals.

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