| CSCI 4150: Introduction to Artificial Intelligence, Fall 2004 |
(define (approx-pi N)
(if (zero? N)
4
(+ (* 4 (/ (expt -1 N) (+ (* 2 N) 1)))
(approx-pi (- N 1)))))
Note that I've multiplied the 4 into the series.
By the way, this series converges very slowly to pi. (For N=300, you will only be accurate to 2 decimal places.) The series in A1p10 converges much quicker.