The denominator in this equation is irrational. This can be seen by the fact that we have a surd (root 3) present, which cannot be expressed as a fraction as is therefore not rational.

In order to rationalise this denominator, we must multiply the fraction by another fraction which will eliminate the presence of the root 3. This must have the denominator of 2 - root 3, as when multiplied, the root 3 is squared and becomes 3. However, in order for this to be possible, the fraction must also have a numerator of 2-root3, so that we are effectively multiplying the fraction by 1. When multiplying, this leaves us with an answer of 28-14 root3, which can be cancelled to 2(14-7root3).