Easy
Symbol √ is used for the following-
Explanation
Explanation
The radical symbol '√' by itself (without a small number written before it) represents the square root of a number — for example, √9 = 3. (A cube root would be written with a small '3' before the symbol, like ∛.) So the correct answer is Square root, option (4).
PRO TIP
Re-check your working by substituting the answer back into the original question.