The equation that represents a tangent function with a domain of all real numbers such that
is 
<h3>Domain</h3>
The domain of a function is the set of input values the function can take
The domain of the function is given as:

<h3>Undefined function</h3>
This means that, we determine the function that would be undefined when the input value equals

From the list of given functions, only function g(x) is undefined at 
Hence, the tangent function is 
Read more about domain at:
brainly.com/question/1770447