How do you simplify sqrt(6)/(4+sqrt(2))?

1 Answer
Mar 3, 2016

(2sqrt(6)-sqrt(3))/6

Explanation:

The idea is to rationalise the denominator, we can do this by multiplying the top and the bottom of the fraction by the conjugate of the bottom:

(4-sqrt(2))/(4-sqrt(2))

We have just took the negative of the square root term.

Now:

sqrt6/(4+sqrt(2))*(4-sqrt(2))/(4-sqrt(2))

=(4sqrt(6)-sqrt2*sqrt6)/(16+4sqrt(2)-4sqrt(2)-2

=(4sqrt(6)-sqrt12)/14

Transform the sqrt(12) term into a surd like so:

=(4sqrt(6)-2sqrt(3))/14=(2sqrt(6)-sqrt(3))/7