Solving an infinite surd..

If an infinite surd is like (√(6+√(6+√(6+√(6...),to solve it, follow these steps: 

Set x = √(6+√(6+√(6+√(6... 

therefore x2 = 6+√(6+√(6+√(6+√(6... 

therefore x2 = 6+x 

therefore 6+x-x2 = 0.
source: How do you solve an infinite surd?