functions3.go

// functions3.go

package main

import (
    "fmt"
    "math"
)

func derivative(f func(float64) float64, a, h float64) float64 {
    return (f(a+h) - f(a)) / h
}

func main() {
    fmt.Println(derivative(math.Sqrt, 2, 0.001))
    fmt.Println(derivative(math.Sin, 2, 0.001))
    f := func(x float64) float64 {
        return x*x*x - x
    }
    fmt.Println(derivative(f, 2, 0.001))
    fmt.Println(derivative(func(x float64) float64 {
        return 1 / x
    }, 2, 0.001))
}