(define (sumsquare a b)
  (if (> a b)
      0
      (+ (* a a) (sumsquare (+ a 1) b)) ))

(define (sumcube a b)
  (if (> a b)
      0
      (+ (* a a a) (sumcube (+ a 1) b)) ))

(define (sum fn a b)
  (if (> a b)
      0
      (+ (fn a) (sum fn (+ a 1) b))))

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

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