#| BEGIN (Write your solution here) |#
(define (repeated f n)
  (define (self x) x)
  (define (compose f g)
  (lambda (x) (f (g x))))
  (if (<= n 0)
      self
      (compose f (repeated f (- n 1)))))

(define (smooth f)
  (let ((dx 0.00001))
    (lambda (x) (/ (+ (f (- x dx))
                      (f x)
                      (f (+ x dx)))
                   3))))
#| END |#