$$\color{rgb(0,127,0)}y=x$$

$$\color{rgb(0,0,255)}\text{C}_{exp}$$

$$\color{rgb(255,0,0)}C_{ln}$$

$$\color{rgb(0,0,255)}a=e^b$$

$$\color{rgb(0,0,0)}b$$

$$\color{rgb(0,0,0)}a$$

$$\color{rgb(255,0,0)}b=\ln a$$