Given
[tex]f(x)=\begin{cases}2x+4;{x<0} \\ 2x+8;x\ge0{}\end{cases}[/tex]
Therefore,
[tex]\begin{gathered} -1<0 \\ \Rightarrow f(-1)=2(-1)+4=-2+4=2 \\ \Rightarrow f(-1)=2 \end{gathered}[/tex]
Similarly,
[tex]\begin{gathered} 0\ge0 \\ \Rightarrow f(0)=2(0)+8=8 \\ \Rightarrow f(0)=8 \\ 2\ge0 \\ \Rightarrow f(2)=2(2)+8=4+8=12 \\ \Rightarrow f(2)=12 \end{gathered}[/tex]
The answers are f(-1)=2, f(0)=8, f(2)=12
