Answer:
The restrictions partly depend on the type of function.
You can’t divide by 0
You can’t take the square (or other even) root of a negative number, as the result will not be a real number.
In what kind of functions would these two issues occur?
the function is a rational function and the denominator is
0
for some value or values of x,
f ( x ) = x + 1 2− x
is a rational function
the function is a radical function with an even index (such as a square root), and the radic and can be negative for some value or values of x.
f ( x ) = √ 7 − x
is a radical function
The following table gives examples of domain restrictions for several different rational functions.
Hope this helped