Question

Fi

Answer 1

The domain of this function includes all x values for which the function is defined. Note that this function is NOT defined at x=-7. Can you explain why? At what other x value is this function not defined?

Now, given this info, can you write the domain of this function in set notation?

Answer 2

this right?
f(x) = sqrt(x+6)/[(x+7)(x-9)]
\[/\large f(x) = \frac{ \sqrt{x+6} }{ (x+7)(x-9) }\]

Answer 3

The domain is the collection of all the values you can put in the function and actually get something back for f(x)

Answer 4

yes thats right function @DanJS

Answer 5

k, so you want to see if there are any values you can put in f(x) that will give you an undefined value.. so you can take those out of the domain

Answer 6

Remember the square root function.. y=sqrt(x) graph??

the values are only 0 or larger, since negative square roots arent in the real numbers...

Answer 7

So, as I was saying, the given function is not defined at x=-7 or at x=?

Draw a number line. Mark these two x values on that line. Set up intervals based upon these two numeric values. Describe the intervals symbolically.

For example, one such interval would be (-infinity, -7).

Please look up "domain" and look for examples of domains.

Answer 8

Dan's example is good: The domain of his function is [0, infinity). Can you explain why?

But that 's just one example of domain.

In the problem at hand, there are two x-values at whicht he function is not defined. Please follow the instructions I gave you earlier.

Answer 9

As you wish. This kind of attitude is not going to get you into Stanford, however.

Answer 10

So be it.

Answer 11

Are you good on what the domain actually is?