This worksheet applies the gradient search method for multi-variable maximization problems. This is an update of our earlier version in the application center. This worksheet solves nonlinear optimization problems by the method of steepest ascent. Given a function f(x,y) and a current point (`x__0`, `y__0`), the search direction is taken to be the gradient of f(x,y) at (`x__0`, `y__0`). The step length is computed by line search, i.e. as the step length that maximizes f(x,y) along the gradient direction.