18 lines
345 B
Scheme
18 lines
345 B
Scheme
#lang sicp
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(define (improve guess x)
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(/ (+ (/ x guess guess)
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(* 2 guess))
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3))
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(define (good-enough? guess x)
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(< (abs (- (improve guess x) guess)) 0.0001))
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(define (cbrt-iter guess x)
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(if (good-enough? guess x)
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guess
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(cbrt-iter (improve guess x)
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x)))
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(define (cube-root x)
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(cbrt-iter 1.0 x))
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