#| BEGIN (Введите свое решение) |#

(define (square x) (* x x))
(define (cube x) (* x x x))

(define (cube-iter guess x)
  (if
   (good-enough? guess x) guess
   (cube-iter (improve guess x) x)
   )
  )

(define (improve guess x)
  (/ (+ (/ x (square guess) ) (* 2 guess)) 3)
)

(define (good-enough? guess x)
   (< (abs (- (cube guess) x))
      0.0001)
)

(define (cube-root x) (cube-iter 1.0 x))
#| END |#