Given the function f (x) = (x 2 cos(x) + sin(x) x), derive the variable step size () that will ensure faster convergence of

Given the function f (x) = (x² cos(x) + sin(x) − x), derive the variable step size (γ) that will ensure faster convergence of the gradient descent method and compare the results with (3)
i) constant step size
ii) decaying step size using various values of α0 and k
iii) Bold driver algorithm