We have to simplify sqrt(2 + sqrt 3) + sqrt(2 - sqrt 3)

Let A = sqrt(2 + sqrt 3) + sqrt(2 - sqrt 3)

A^2 = (sqrt(2 + sqrt 3) + sqrt(2 - sqrt 3))^2

=> 2 + sqrt 3 + 2 - sqrt 3 + 2*sqrt(2 + sqrt 3)sqrt(2 - sqrt 3)

=> 4 + 2*(2^2 - (sqrt 3)^2)

=> 4 + 2*(4 - 3)

=> 6

A = sqrt 6

**sqrt(2 + sqrt 3) + sqrt(2 - sqrt 3) = sqrt 6**