Find the domain of f for each of the following functions. If you need to enter - or , enter -INFINITY or INFINITY.

f(x)= sqrt(64-x^2)

Question

Find the domain of f for each of the following functions. If you need to enter - or , enter -INFINITY or INFINITY.

f(x)= sqrt(64-x^2)

anonymous · Answer

you have to make sure that 
$$64-x^2\geq 0$$ 
the graph of 
$$y=64-x^2$$ is a parabola facing down, therefore it will be positive between the zeros and negative outside (think of the picture).  the zeros are -8 and 8 so it is positive between -8 and 8
  your answer is 
$$[-8,8]$$

anonymous · Answer

Oh okay, I understand now. Thank you!