(define fact (lambda (n) (cond ((= n 0) 1) ((= n 1) 1) (#t (* n (fact (- n 1))))))) (define fact (lambda (n) (letrec ((factHelper (lambda (n productThusFar) (cond ((= n 0) productThusFar) ((= n 1) productThusFar) (#t (factHelper (- n 1) (* n productThusFar))))))) (factHelper n 1))))