自然指数函数的泰勒级数展开:
$$ e^x = 1 + x + \frac{x^2}{2!} + \frac{x^3}{3!} + \frac{x^4}{4!} + \cdots $$
正弦函数的泰勒级数展开:
$$ \sin(x) = x - \frac{x^3}{3!} + \frac{x^5}{5!} - \frac{x^7}{7!} + \cdots $$
余弦函数的泰勒级数展开:
$$ \cos(x) = 1 - \frac{x^2}{2!} + \frac{x^4}{4!} - \frac{x^6}{6!} + \cdots $$
自然对数的泰勒级数展开:
$$ \ln(1 + x) = x - \frac{x^2}{2} + \frac{x^3}{3} - \frac{x^4}{4} + \cdots $$
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39
| (define (factorial n) (if (= n 0) 1 (* n (factorial (- n 1)))))
(define (exp-taylor x terms) (if (= terms 0) 0 (+ (/ (expt x (- terms 1)) (factorial (- terms 1))) (exp-taylor x (- terms 1)))))
(define (sin-taylor x terms) (if (= terms 0) 0 (let ([term-num (sub1 (* 2 terms))]) (+ (* (if (even? terms) -1 1) (/ (expt x term-num) (factorial term-num))) (sin-taylor x (- terms 1))))))
(define (cos-taylor x terms) (if (= terms 0) 1 (let ([term-num (sub1 (* 2 terms))]) (+ (* (if (even? terms) 1 -1) (/ (expt x term-num) (factorial term-num))) (cos-taylor x (- terms 1))))))
(define (ln-taylor x terms) (if (= terms 0) 0 (+ (* (if (even? terms) -1 1) (/ (expt x terms) terms)) (ln-taylor x (- terms 1)))))
(exp-taylor 1 10) (sin-taylor 1 10) (cos-taylor 1 10) (ln-taylor 0.5 10)
|