Question

PLEASE HELP ME!!
Find the domain, in interval notation too.

Answer 1

`D = (-\infty, -1) \ \cup \ (-1, 2) \ \cup \ (2, \infty)`

Explanation:

This function is rational function that's meaning that is of the form:

`(1)/(x)`

So you have to take care when
`x` is equal to 0 because the function is undefine in that number (is represented with an asymptote and means that go to positive or negative infinity).

In the given graph there are 2 asymptotes in -1 and 2 so you have to avoid this two points in the notations by intervals. You can achieve this using the parenthesis indicating that you don't take the value in account.

Answer 2

I sadly do not have an answer to this problem but, have a great explanation for a similar problem. (I really am sorry that I don't have the answer, in a bit of a time constraint)

Explanation:

Example (graph found below):

The domain of a function f(x) is the set of values of x for which f(x) has a defined value.



In the graph we can see that we have two asymptotes: one vertical and one slant asymptote.



The slant asymptote does not affect the domain, but the vertical asymptote at x = 0 implies that f(x) does not have a defined value at x = 0.

Then, x = 0 is not part of the domain of f(x). All the real numbers different from 0 are part of the domain.



Then, we can write the domain as x ≠ 0 or, in interval notation, as (-∞,0) ∪ (0,∞).



Answer: the domain is all the real numbers different from 0.



NOTE:

If we want to know the range of the function, we have to look at the values that f(x) can take for the domain for which it is defined.

In this case, we can see that there is no limitation for the values f(x) can take: f(x) can take all real numbers, so the range is all real numbers.