Don't use bit representation of float64 as it don't make sense in a lot of cases. Just subtract two numbers to find out how much they differ:
package main
import (
"fmt"
"math"
)
const float64EqualityThreshold = 1e-9
func almostEqual(a, b float64) bool {
return math.Abs(a - b) <= float64EqualityThreshold
}
func main() {
a := 0.1
b := 0.2
fmt.Println(almostEqual(a + b, 0.3))
}