To solve this problem you must apply the proccedure shown below:
1- You have the following radical expression given in the problem above:
(√7)(√(14)+√(3))
2- When you apply the distributive property, you obtain:
(√7)(√(14))+ (√7)(√(3))
3-Simpliying, you have:
(7√2)+(√21)
4- Therefore the answer is: (7√2)+(√21)