Steepest descent method to minimize a differentiable function of 2 variables

The negative of the gradient (vector partial derivatives) of a differentiable function evaluated at a point (x1, x2) points in the direction of the fastest instantaneous rate of decrease of the function. This fact can be used to generate a sequence of points that leads to smaller and smaller values of the function. It is one of the first algorithms introduced in nonlinear programming courses. Reference: https://mathworld.wolfram.com/MethodofSteepestDescent.html