Laws of Indices
Surds are basically an expression involving a root, squared or cubed etc...
There are some basic rules when dealing with surds
Also notice the special case
Difference of Two Squares
When you have a fraction where both the nominator and denominator are surds, rationalising the surd is the process of getting rid of the surd on the denominator.
To rationalise a surd you multiply top and bottom by fraction that equals one. Take the example shown below
To rationalise this multiply by effectively 1
For a more complex term
First of all, we need to get rid of the surd expression on the bottom, you should remember the difference of two squares formula.