\partialThe symbol \partial is used to denote partial derivatives in calculus. It represents the derivative of a function with respect to one of its variables, while keeping the other variables constant. This is commonly used in multivariable calculus and differential equations.
Partial derivative of function f with respect to variable x.
\frac{\partial f}{\partial x}Second partial derivative of function f with respect to variable x.
\frac{\partial^2 f}{\partial x^2}Mixed partial derivative of function f with respect to variables x and y.
\frac{\partial^2 f}{\partial x \partial y}