题解 | #求解立方根#
求解立方根
https://www.nowcoder.com/practice/caf35ae421194a1090c22fe223357dca
牛顿法：
要求 %3Dy)
的解，记 %20%3D%20f(x)%20-y)
，牛顿法求根：
package main
import (
"fmt"
"math"
)
func main(){
var n float64
fmt.Scanf("%f", &n)
x0 := 3.0
x1 := 1.0
for math.Abs(x1-x0) > 1e-2{
x1, x0 = x0-(x0*x0*x0 - n)/(3*x0*x0), x1
}
fmt.Printf("%.1f", x1)
}
简单点：
package main
import "fmt"
import "math"
func main(){
var num float64
fmt.Scanln(&num)
precise := 1e-3
t := num
for math.Abs(t*t*t - num) > precise{
t = t - (t*t*t - num)/(3*t*t)
}
fmt.Printf("%.1f", t)
}
