Golden Ratio by Fixed Point of a Function

The golden ratio is a fixed point of the transformation x 1 + 1/x. The code below uses this to compute it.

	(define tolerance 0.00001)
	(define (fixed-point f first-guess)
	(define (close-enough? v1 v2)
	(< (abs (- v1 v2)) tolerance))
	(define (try guess)
	(let ((next (f guess)))
	(if (close-enough? guess next)
	next
	(try next))))
	(try first-guess))
	(define f (lambda (x) (+ 1 (/ 1 x))))
	(fixed-point f 1.0)

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