Calculadora de Derivadas Parciais

Your input: find $$$\frac{\partial}{\partial y}\left(e^{x y}\right)$$$

Write the function $$$e^{x y}$$$ as a composition of the two functions $$$u=g=x y$$$ and $$$f\left(u\right)=e^{u}$$$.

Apply the chain rule $$$\frac{\partial}{\partial y} \left(f\left(g\right) \right)=\frac{\partial}{\partial u} \left(f\left(u\right) \right) \cdot \frac{\partial}{\partial y} \left(g \right)$$$:

$${\color{red}{\frac{\partial}{\partial y}\left(e^{x y}\right)}}={\color{red}{\frac{\partial}{\partial u}\left(e^{u}\right) \frac{\partial}{\partial y}\left(x y\right)}}$$

The derivative of an exponential is $$$\frac{\partial}{\partial u} \left(e^{u} \right)=e^{u}$$$:

$${\color{red}{\frac{\partial}{\partial u}\left(e^{u}\right)}} \frac{\partial}{\partial y}\left(x y\right)={\color{red}{e^{u}}} \frac{\partial}{\partial y}\left(x y\right)$$

Return to the old variable:

$$e^{{\color{red}{u}}} \frac{\partial}{\partial y}\left(x y\right)=e^{{\color{red}{x y}}} \frac{\partial}{\partial y}\left(x y\right)$$

Apply the constant multiple rule $$$\frac{\partial}{\partial y} \left(c \cdot f \right)=c \cdot \frac{\partial}{\partial y} \left(f \right)$$$ with $$$c=x$$$ and $$$f=y$$$:

$$e^{x y} {\color{red}{\frac{\partial}{\partial y}\left(x y\right)}}=e^{x y} {\color{red}{x \frac{\partial}{\partial y}\left(y\right)}}$$

Apply the power rule $$$\frac{\partial}{\partial y} \left(y^{n} \right)=n\cdot y^{-1+n}$$$ with $$$n=1$$$, in other words $$$\frac{\partial}{\partial y} \left(y \right)=1$$$:

$$x e^{x y} {\color{red}{\frac{\partial}{\partial y}\left(y\right)}}=x e^{x y} {\color{red}{1}}$$

Thus, $$$\frac{\partial}{\partial y}\left(e^{x y}\right)=x e^{x y}$$$

Answer: $$$\frac{\partial}{\partial y}\left(e^{x y}\right)=x e^{x y}$$$