Final answer:
The opposite of 3√ is -3√.
Step-by-step explanation:
The opposite of 3√ is -3√ (option a).
When we talk about the opposite of a number, we are referring to its additive inverse. In this case, 3√ is a positive number, so its opposite would be a negative number with the same absolute value.
For example, if we have 3x, the opposite of 3x would be -3x. Similarly, the opposite of 3√ is -3√.