Question
Find the domain of the function. Write in interval notation.
sqrt(x^2 − 64).
For the answer, I got (-infinity, -8)u(8, infinity), but that's wrong, and I'm not sure what else to try?
sqrt(x^2 − 64).
For the answer, I got (-infinity, -8)u(8, infinity), but that's wrong, and I'm not sure what else to try?
Answers
bobpursley
if you allow taking imaginary roots, then the domain is -inf to +inf.
If you allow only real roots, then must be less than -8 or greater than 8, your answer.
consider x=3
sqrt(9-64)=sqrt(-55)=i*sqrt55
If you allow only real roots, then must be less than -8 or greater than 8, your answer.
consider x=3
sqrt(9-64)=sqrt(-55)=i*sqrt55