Piecewise Function Evaluation
Given the function

f(x)={6x+2x<06x+4x0\displaystyle {f{{\left({x}\right)}}}={\left\lbrace\begin{array}{cc} {6}{x}+{2}&{x}<{0}\\{6}{x}+{4}&{x}\geq{0}\end{array}\right.}

Calculate the following values:
f(1)=\displaystyle {f{{\left(-{1}\right)}}}=  
f(0)=\displaystyle {f{{\left({0}\right)}}}=  
f(2)=\displaystyle {f{{\left({2}\right)}}}=