What is the domain of [tex]f(x)=\frac{-4}{x}+1[/tex]?

A. [tex](-\infty, 1) \cup(1, \infty)[/tex]
B. [tex](-\infty, \infty)[/tex]
C. [tex](-\infty, -1) \cup(-1, \infty)[/tex]
D. [tex](-\infty, 0) \cup(0, \infty)[/tex]



Answer :

To determine the domain of the function [tex]\( f(x) = \frac{-4}{x} + 1 \)[/tex], we need to identify all values of [tex]\( x \)[/tex] for which the function [tex]\( f(x) \)[/tex] is defined.

### Step-by-Step Solution:

1. Identify Points Where the Function is Undefined:
The function [tex]\(\frac{-4}{x} + 1\)[/tex] will be undefined wherever the denominator [tex]\( x \)[/tex] is zero since division by zero is undefined.

Setting the denominator equal to zero:
[tex]\[ x = 0 \][/tex]
Therefore, the function [tex]\( f(x) \)[/tex] is undefined at [tex]\( x = 0 \)[/tex].

2. Determine the Domain:
The domain of [tex]\( f(x) \)[/tex] includes all real numbers except those for which the function is undefined.

Since the function is undefined at [tex]\( x = 0 \)[/tex], we need to exclude this point from the real number line.

As a result, the domain of the function is all real numbers excluding [tex]\( x = 0 \)[/tex]. In interval notation, this is written as:
[tex]\[ (-\infty, 0) \cup (0, \infty) \][/tex]

3. Verify the Domain:
We can summarize the domain by saying that [tex]\( x \)[/tex] can take any real number value except [tex]\( x = 0 \)[/tex], confirming our previously written interval notation.

### Conclusion:
By analyzing the points of undefinedness and constructing the correct intervals, we conclude that the domain of [tex]\( f(x) = \frac{-4}{x} + 1 \)[/tex] is:
[tex]\[ (-\infty, 0) \cup (0, \infty) \][/tex]

### Correct Answer:
The correct answer is:
[tex]\[ \boxed{D. \, (-\infty, 0) \cup (0, \infty)} \][/tex]