$$f\left(x\right)=3x-1$$  

$$f\left(x\right)=\frac{1}{2}x$$  

$$f\left(x\right)=-\frac{x}{3}$$  

$$f\left(x\right)=2$$  

$$f\left(x\right)=x$$  

$$f\left(x\right)=x^2-1$$  

$$f\left(x\right)=\frac{1}{4}\left(x-1\right)^2$$  

$$f\left(x\right)=-1-x^2$$  

$$f\left(x\right)=\sqrt[]{x-3}$$  

$$f\left(x\right)=-\sqrt[]{-x}$$  

$$f\left(x\right)=-\frac{3}{x}$$  

$$f\left(x\right)=\frac{1}{2x}$$  

$$f\left(x\right)=\frac{1}{x+1}$$  

$$f\left(x\right)=\frac{1}{x}+1$$  

$$f\left(x\right)=\sqrt[]{x}+2$$  

$$f\left(x\right)=3x-1$$  

$$f\left(x\right)=\frac{1}{2}x$$  

$$f\left(x\right)=\frac{x}{3}$$  

$$f\left(x\right)=2$$  

$$f\left(x\right)=x$$  

$$f\left(x\right)=x^2$$  

$$f\left(x\right)=-\sqrt[]{-x}$$  

$$f\left(x\right)=\frac{3}{x}$$  

$$f\left(x\right)=\frac{1}{2x}$$