SICP Exercise 1.42

Question

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

copy((compose square inc) 6)
49

Answer

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

(define (compose f g)
  (λ (x) (f (g x))))

((compose square inc)  6)

Result:

copy49