SOLUTION: Let the function f be defined by the equation y = f(x), where x and f(x) are real numbers. Find the domain of the function. f(x)= sqrt of x^2-64 (the sqrt is of the x^2-

Algebra ->  Functions -> SOLUTION: Let the function f be defined by the equation y = f(x), where x and f(x) are real numbers. Find the domain of the function. f(x)= sqrt of x^2-64 (the sqrt is of the x^2-      Log On


   

Question 389281: Let the function f be defined by the equation y = f(x), where x and f(x) are real numbers. Find the domain of the function.
f(x)= sqrt of x^2-64


(the sqrt is of the x^2-64 not just the x^2)
Answer by richard1234(7193) About Me  (Show Source):
You can put this solution on YOUR website!
We have

f%28x%29+=+sqrt%28x%5E2+-+64%29

For the function to be defined on the real numbers, the square root expression must be nonnegative. Therefore,

x%5E2+-+64+%3E=+0

x%5E2+%3E=+64

x+%3E=+8 or x+%3C=+-8