Answer:
[tex]\boxed{\sf all \ real \ numbers \ greater \ than \ or \ equal \ to \ 0}[/tex]
Step-by-step explanation:
The domain of a function is all possible values for x.
[tex]\sf f(x)=\frac{2}{5} \sqrt{x}[/tex]
There are restrictions on x.
The square root of a number can be undefined if that number is less than 0.
The value of x is all real numbers greater than or equal to 0.
