Exercise 1.3

sicp-1-3.lisp

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

(define (sum-of-squares x y) (+ (square x) (square y)))

(define (larger x y) (if (> x y) x y))

(define (sum-squares-of-largest-two x y z) 
  (cond ((and (> x y) (> x z)) (sum-of-squares x (larger y z)))
        ((and (> y x) (> y z)) (sum-of-squares y (larger x z)))
        (else (sum-of-squares z (larger x y)))
       ))

(= 41 (sum-squares-of-largest-two 3 4 5))