sicp 1.42

Exercise 1.42.  Let f and g be two one-argument functions. The composition f after g is defined to be the function x f(g(x)). Define a procedure compose that implements composition. For example, if inc is a procedure that adds 1 to its argument,

 

((compose square inc) 6)
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(define (compose f g)
  (lambda (x)
    (f (g x))))

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

(define (inc x)
  (+ x 1))

((compose square inc) 6)

 

49