Question 309016
Let us first find the product of 
(2√3) x (√5)
= 2√15

Now let us try to add

(4 / 2√3) + (1 / √5)
= (4 x √5 / 2√3 x √5) + (1 x 2√3 /√5 x 2√3)
= 4√5 / 2√15 + 2√3 / 2√15

Now that the denominators are equal we can add the numerators

= (4√5 + 2√3) / 2√15
 We take out the common factor from the numerator

= 2(2√5 + √3) / 2√15

We cross out the factor 2 from the numerator and denominator

= (2√5 + √3) / √15