New to Go, trying to see if the following error handling method can be further improved?

package main

import (
    "fmt"
    "math"
)

type ErrNegativeSqrt float64

func (e ErrNegativeSqrt) Error() string {
    return fmt.Sprintf("cannot Sqrt negative number: %f", float64(e))
}

func Sqrt(f float64) (float64, error) {
    if f > 0 {
        return math.Sqrt(f), nil
    } else {
        return 0, ErrNegativeSqrt(f)
    }
}

func main() {
    fmt.Println(Sqrt(2))
    fmt.Println(Sqrt(-2))
}

New to Go, trying to solve Tour of Go, Exercise 56, which is about error handling.

Can the following error handling method can be further improved?

package main

import (
    "fmt"
    "math"
)

type ErrNegativeSqrt float64

func (e ErrNegativeSqrt) Error() string {
    return fmt.Sprintf("cannot Sqrt negative number: %f", float64(e))
}

func Sqrt(f float64) (float64, error) {
    if f > 0 {
        return math.Sqrt(f), nil
    } else {
        return 0, ErrNegativeSqrt(f)
    }
}

func main() {
    fmt.Println(Sqrt(2))
    fmt.Println(Sqrt(-2))
}