The given functions are
[tex]\begin{gathered} f(x)=2x+1 \\ g(x)=x-6 \end{gathered}[/tex]
Notice that g/f has the function f(x) as denominator which can't be zero otherwise the division won't be defined, so let's solve f(x) when is equal to zero.
[tex]\begin{gathered} 2x+1=0 \\ 2x=-1 \\ x=-\frac{1}{2} \end{gathered}[/tex]
Therefore, the restriction of g/f is option 4.
