# Math Help - Surds

1. ## Surds

4+ √5
------
3+ √2

I could work that out as:

12 - 4 √2 + 3 √5 - √10
-------------------------
7

But If the surd had a number in front of one, e.g:

4 + 4 √5
--------
3 + √2

How would that change it?

2. Originally Posted by db5vry

4+ √5
------
3+ √2

I could work that out as:

12 - 4 √2 + 3 √5 - √10
-------------------------
7

But If the surd had a number in front of one, e.g:

4 + 4 √5
--------
3 + √2

How would that change it?
The numerator would be $(4+4\sqrt{5})(3-\sqrt{2})=12+12\sqrt{5}-4\sqrt{2}-4\sqrt{10}$

The denominator wouldn't change.