How do you find the domain of #f (x) = sqrt( -x) / [(x - 3) (x + 5)]#?
1 Answer
Apr 4, 2018
What is the domain? The domain is the range of numbers when substituted gives a valid answer and not undefined
Now, it would be undefined if the denominator was equal to 0
So,
So these numbers are not part of the domain
This would also be undefined if the number under the root was negative.
So for
So all positive numbers are also not part of the domain
So as we can see, the numbers that make it undefined are all positive numbers
Hence the domain is all negative numbers inclusive of 0.