SOLUTION: The domain of the function f(x)=∛(16-x^2 ) is all real numbers but how do you get to that answer?

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Question 678244: The domain of the function f(x)=∛(16-x^2 ) is all real numbers but how do you get to that answer?
Answer by pmatei(79) About Me  (Show Source):
You can put this solution on YOUR website!
The number under a cube root it is not restricted to just non-negative numbers as for the one under the square root.
∛(-64) = -4 because %28-4%29%5E3+=+-64.
∛(64) = 4 because 4%5E3=+64.
Thus 16-x%5E2 can be anything you want: negative, zero, or positive number. Which means you can plug any number you want for x, thus the domain is all real numbers.