Third order partial derivative of f(x,y)

Question

Write all the possible third order partial derivatives of the function of two variables f(x,y).

Answer 1

Write third order partial derivatives of the function.

​(∂/∂​​x)(∂²f/∂y∂x) =∂³f/∂x∂y∂x = ∂³f/∂x²∂y

​(∂/∂​​x)(∂²f/∂x∂y) =∂³f/∂x∂x∂y = ∂³f/∂x²∂y