Answer:
c:(0;+∞)
Step-by-step explanation:
Given the situation, that the square root function only allows you values above than "0" (not equal neither), then you must consider that every value above 0 belongs to it's domain.
Then, to express the domain, going from your most negative number, to your most possitive number (in this case all positive number, thats why we use infinite) you must use the parenthesis wich means, you are not considering the value (in this case 0), but the value right after it, to the next value that as we said before, is inifinite. Also remember, that when you express a domain, and use infinite (despite it's going to negative way, or possitive way, it also goes with parenthesis).
